WDIFF

draft-ietf-policy-core-info-model-01.txt --> draft-ietf-policy-core-info-model-02.txt

INTERNET-DRAFT E. Ellesson
Category: Standards Track IBM
J. Strassner
Cisco Systems
October 1999

Policy Framework Core Information Model

<draft-ietf-policy-core-info-model-01.txt>
Tuesday,

<draft-ietf-policy-core-info-model-02.txt>
Friday, October 05, 22, 1999, 3:15 1:22 PM

Status of this Memo

This document is an Internet-Draft and is in full conformance with all
provisions of Section 10 of RFC2026.

Internet-Drafts are working documents of the Internet Engineering Task
Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.

Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."

The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt

The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html

Abstract

This document presents the object-oriented information model for
representing policy information currently under development as part of
the Common Information Model (CIM) activity in the Distributed
Management Task Force (DMTF). This CIM model defines two hierarchies
of object classes: structural classes representing policy information
and control of policies, and relationship classes that indicate how
instances of the structural classes are related to each other. A
companion document "Policy Framework Core LDAP Schema" [9] defines the
mapping of this information model to a directory that uses LDAPv3 as
its access protocol.

Moore, et al. Expires: Oct 1999 + 6 months [Page 1]

Internet Draft Policy Core Information Model October 1999

Table of Contents

1. Introduction......................................................4
2. Modeling Policies.................................................5 Policies.................................................6
2.1. Policy Scope.................................................7 Scope.................................................8
2.2. Declarative versus Procedural Model..........................8
3. Overview of the Policy Core Information Model.....................9 Model....................10
4. Inheritance Hierarchies for the Core Policy Classes and
Relationships.......................................................12
Relationships.......................................................13
5. Details of the Model.............................................14 Model.............................................15
5.1. Reusable versus Rule-Specific Conditions and Actions........14 Actions........16
5.2. Roles and Resource Managers.................................17
5.3. Naming in the Policy Core Information Model.................15
5.2.1. Model.................18
5.3.1. Role of the CreationClassName Property in Naming..........18
5.3.2. Naming Instances of PolicyGroup and PolicyRule............15
5.2.2. PolicyRule............19
5.3.3. Naming Instances of PolicyCondition and Its Subclasses....16
5.2.3. Subclasses....20
5.3.4. Naming Instances of PolicyAction and Its Subclasses.......18
5.3. Subclasses.......22
5.3.5. Naming Instances of PolicyRepository and
ResourceManagerCollection........................................22
5.4. CIM Data Types..............................................18 Types..............................................22
6. Class Definitions................................................18 Definitions................................................23
6.1. The Abstract Class "Policy".................................19 "Policy".................................23
6.1.1. The Property "CommonName (CN)"............................19 (CN)"............................24
6.1.2. The Multi-valued Property "Caption"....................................20 "PolicyKeywords"................24
6.1.3. The Property "Description"................................20 "Caption" (Inherited from ManagedElement)....25
6.1.4. The Multi-valued Property "PolicyKeywords"................20 "Description" (Inherited from ManagedElement)25
6.2. The Class "PolicyGroup".....................................21 "PolicyGroup".....................................25
6.2.1. The Propagated Key Property "System.CreationClassName"....22 "System.CreationClassName"....26
6.2.2. The Propagated Key Property "System.Name".................22 "System.Name".................27
6.2.3. The Key Property "PolicyGroupName"........................22 "CreationClassName"......................27
6.2.4. The Key Property "PolicyGroupName"........................27
6.3. The Class "PolicyRule"......................................23 "PolicyRule"......................................27
6.3.1. The Propagated Key Property "System.CreationClassName"....24 "System.CreationClassName"....29
6.3.2. The Propagated Key Property "System.Name".................24 "System.Name".................29
6.3.3. The Key Property "PolicyRuleName".........................25 "CreationClassName"......................30
6.3.4. The Key Property "Enabled"....................................25 "PolicyRuleName".........................30
6.3.5. The Property "ConditionListType"..........................25 "Enabled"....................................30
6.3.6. The Property "RuleUsage"..................................26 "ConditionListType"..........................31
6.3.7. The Property "Priority"...................................26 "RuleUsage"..................................31
6.3.8. The Property "Mandatory"..................................26 "Priority"...................................31
6.3.9. The Property "SequencedActions"...........................27 "Mandatory"..................................31
6.3.10. The Property "SequencedActions"..........................32
6.4. The Class "PolicyCondition".................................27 "PolicyCondition".................................33
6.4.1. The Key Property "SystemCreationClassName"................29 "SystemCreationClassName"................34
6.4.2. The Key Property "SystemName".............................29 "SystemName".............................35
6.4.3. The Key Property "PolicyRuleName".........................30 "PolicyRuleCreationClassName"............35
6.4.4. The Key Property "PolicyConditionName"....................30 "PolicyRuleName".........................36
6.4.5. The Key Property "CreationClassName"......................36
6.4.6. The Key Property "PolicyConditionName"....................36
6.5. The Class "PolicyTimePeriodCondition".......................30 "PolicyTimePeriodCondition".......................37
6.5.1. The Property "TimePeriod".................................32 "TimePeriod".................................38
6.5.2. The Property "MonthOfYearMask"............................32 "MonthOfYearMask"............................39

Moore, et al. Expires: Oct 1999 + 6 months [Page 2]

Internet Draft Policy Core Information Model October 1999

6.5.3. The Property "DayOfMonthMask".............................33 "DayOfMonthMask".............................39
6.5.4. The Property "DayOfWeekMask"..............................33 "DayOfWeekMask"..............................41
6.5.5. The Property "TimeOfDayMask"..............................34 "TimeOfDayMask"..............................41
6.5.6. The Property "ApplicableTimeZone".........................35 "ApplicableTimeZone".........................42
6.6. The Class "VendorPolicyCondition"...........................35 "VendorPolicyCondition"...........................43
6.6.1. The Multi-valued Property "Constraint"....................36 "Constraint"....................43
6.6.2. The Property "ConstraintEncoding".........................36 "ConstraintEncoding".........................44
6.7. The Class "PolicyAction"....................................37

Moore, et al. Expires: Oct 1999 + 6 months [Page 2]

Internet Draft Policy Core Information Model October 1999 "PolicyAction"....................................44
6.7.1. The Key Property "SystemCreationClassName"................37 "SystemCreationClassName"................45
6.7.2. The Key Property "SystemName".............................38 "SystemName".............................45
6.7.3. The Key Property "PolicyRuleName".........................38 "PolicyRuleCreationClassName"............46
6.7.4. The Key Property "PolicyActionName".......................39 "PolicyRuleName".........................46
6.7.5. The Key Property "CreationClassName"......................46
6.7.6. The Key Property "PolicyActionName".......................47
6.8. The Class "VendorPolicyAction"..............................39 "VendorPolicyAction"..............................47
6.8.1. The Multi-valued Property "ActionData"....................39 "ActionData"....................47
6.8.2. The Property "ActionEncoding".............................40 "ActionEncoding".............................48
6.9. The Class "PolicyRepository"................................40 "PolicyRepository"................................48
6.9.1. The Key Property "CreationClassName"......................49
6.9.2. The Key Property "PolicyRepositoryName"...................49
6.10. The Class "ResourceManagerCollection"......................49
6.10.1. The Key Property "CreationClassName".....................49
6.10.2. The Key Property "ResourceManagerCollectionName".........50
6.10.3. The Multi-valued Property "ResourceManagerType"..........50
7. Association and Aggregation Definitions..........................40 Definitions..........................50
7.1. Relationships...............................................41 Relationships...............................................50
7.2. Associations................................................41 Associations................................................51
7.3. Aggregations................................................41 Aggregations................................................51
7.4. The Aggregation "PolicyGroupInPolicyGroup"..................41 "PolicyGroupInPolicyGroup"..................51
7.4.1. The Reference "ContainingGroup"...........................42 "ContainingGroup"...........................51
7.4.2. The Reference "ContainedGroup"............................42 "ContainedGroup"............................52
7.5. The Aggregation "PolicyRuleInPolicyGroup"...................42 "PolicyRuleInPolicyGroup"...................52
7.5.1. The Reference "ContainingGroup"...........................42 "ContainingGroup"...........................52
7.5.2. The Reference "ContainedRule".............................43 "ContainedRule".............................52
7.6. The Aggregation "ConditionInPolicyRule".....................43 "ConditionInPolicyRule".....................52
7.6.1. The Reference "ContainingRule"............................43 "ContainingRule"............................53
7.6.2. The Reference "ContainedCondition"........................44 "ContainedCondition"........................53
7.6.3. The Property "GroupNumber"................................44 "GroupNumber"................................54
7.6.4. The Property "ConditionNegated"...........................44 "ConditionNegated"...........................54
7.7. The Aggregation "PolicyRuleValidityPeriod"..................45 Association "ConditionSubject"..........................54
7.7.1. The Reference "ContainingRule"............................45 "Subject"...................................55
7.7.2. The Reference "ContainedPtp"..............................45 "Condition".................................55
7.8. The Aggregation "ActionInPolicyRule"........................45 Association "ConditionTarget"...........................55
7.8.1. The Reference "ContainingRule"............................46 "Target"....................................56
7.8.2. The Reference "ContainedAction"...........................46
7.8.3. The Property "ActionOrder"................................46 "Condition".................................56
7.9. The Aggregation "ConditionInPolicyRepository"...............47 "PolicyRuleValidityPeriod"..................56
7.9.1. The Reference "ContainingRepository"......................48 "ContainingRule"............................57
7.9.2. The Reference "ContainedCondition"........................48 "ContainedPtp"..............................57
7.10. The Aggregation "ActionInPolicyRepository".................48 "ActionInPolicyRule".......................57
7.10.1. The Reference "ContainingRepository".....................48 "ContainingRule"...........................58
7.10.2. The Reference "ContainedAction"..........................49 "ContainedAction"..........................58
7.10.3. The Property "ActionOrder"...............................58

Moore, et al. Expires: Oct 1999 + 6 months [Page 3]

Internet Draft Policy Core Information Model October 1999

7.11. The Weak Aggregation "PolicyGroupInSystem".................49 Association "ConditionInPolicyRepository"..............59
7.11.1. The Reference "ContainingSystem".........................49 "ContainingRepository".....................59
7.11.2. The Reference "ContainedGroup"...........................49 "ContainedCondition".......................59
7.12. The Weak Aggregation "PolicyRuleInSystem"..................49 Association "ActionInPolicyRepository".................60
7.12.1. The Reference "ContainingSystem".........................50 "ContainingRepository".....................60
7.12.2. The Reference "ContainedRule"............................50 "ContainedAction"..........................60
7.13. The Aggregation "PolicyRepositoryInPolicyRepository".......50 Weak Association "PolicyGroupInSystem".................60
7.13.1. The Reference "ContainingRepository".....................50 "ContainingSystem".........................61
7.13.2. The Reference "ContainedRepository"......................51 "ContainedGroup"...........................61
7.14. The Policy Group Jurisdiction Associations.................51 Weak Association "PolicyRuleInSystem"..................61
7.14.1. The Reference "GroupScope"...............................51 "ContainingSystem".........................61
7.14.2. The Reference "ApplicableGroup"..........................52 "ContainedRule"............................61
7.15. The Policy Rule Jurisdiction Associations..................52 Aggregation "PolicyRepositoryInPolicyRepository".......62
7.15.1. The Reference "RuleScope"................................52 "ContainingRepository".....................62
7.15.2. The Reference "ApplicableRule"...........................52 "ContainedRepository"......................62
7.16. The Policy Repository Jurisdiction Associations............53

Moore, et al. Expires: Oct 1999 + 6 months [Page 3]

Internet Draft Policy Core Information Model October 1999

7.16.1. Association "ResourceManagerCollectionPolicyGroup".....62
7.17. The Reference "RepositoryScope"..........................53
7.16.2. Association "ResourceManagerCollectionPolicyRule"......63
7.18. The Reference "ApplicableRepository".....................53 Aggregation "MemberResourceManager"....................63
7.19. The Association "ResourceManagerPolicyGroup"...............64
7.20. The Association "ResourceManagerPolicyRule"................64
7.21. The Association "ResourceManagerManagedResource"...........64
8. Intellectual Property............................................54 Property............................................64
9. Acknowledgements.................................................54 Acknowledgements.................................................65
10. Security Considerations.........................................54 Considerations.........................................65
11. References......................................................56 References......................................................67
12. Authors' Addresses..............................................57 Addresses..............................................68
13. Full Copyright Statement........................................57 Statement........................................68

1. Introduction

+-------------------------------------------------------------------+
|NOTE: Because of the short time between the most recent DMTF WG |
| meetings and the IETF's Internet-Draft cutoff date, this |
| document has been updated without a corresponding update |
| to the LDAP Core Schema document. Thus this document, |
| <draft-ietf-policy-core-info-model-02.txt>, is temporarily |
| out of step with <draft-ietf-policy-core-schema-05.txt>. |
| The goal is to get the documents back in sync by publishing |
| <draft-ietf-policy-core-schema-06.txt>, after the Internet- |
| Draft cutoff, but prior to the Washington IETF. A URL for |
| retrieving this updated document will be sent to the Policy |
| mailing list. |
+-------------------------------------------------------------------+

Moore, et al. Expires: Oct 1999 + 6 months [Page 4]

Internet Draft Policy Core Information Model October 1999

instances of the structural classes are related to each other. A
companion document "Policy Framework Core LDAP Schema" [9] defines the
mapping of this information model to a directory that uses LDAPv3 as
its access protocol.

The policy classes and relationships defined in the CIM model are
sufficiently generic to allow them to represent policies related to
anything. However, it is expected that their initial application in
the IETF will be for representing policies related to QoS (DiffServ
and IntServ) and to IPSec. Policy models for application-specific
areas such as these may extend the Core Model in several ways. The
preferred way is to use the PolicyGroup, PolicyRule, and
PolicyTimePeriodCondition classes directly, as a foundation for
representing and communicating policy information. Then, specific
subclasses derived from PolicyCondition and PolicyAction can capture
application-specific definitions of conditions and actions of
policies.

Two subclasses, VendorPolicyCondition and VendorPolicyAction, are also
included in this document, to provide a standard escape mechanism for
vendor-specific extensions to the Policy Core Information Model.

This document fits into the overall framework for representing,
deploying, and managing policies being developed by the Policy
Framework Working Group. The initial work to define this framework is
in reference [1]. More specifically, this document builds on the core
policy classes first introduced in references [2] and [3]. It also
draws on the work done for the Directory-enabled Networks (DEN)
specification, reference [4]. Work on the DEN specification by the
DEN Ad-Hoc Working Group itself has been completed. Further work to
standardize the models contained in it will be the responsibility of
selected working groups of the CIM effort in the Distributed

Moore, et al. Expires: Oct 1999 + 6 months [Page 4]

Internet Draft Policy Core Information Model October 1999
Management Task Force (DMTF). Standardization of the core policy
model is the responsibility of the SLA Policy working group.

This document is organized in the following manner:

o Section 2 provides a general overview of policies and how they are
modeled.

o Section 3 presents a high-level overview of the classes and
relationships comprising the Policy Core Information Model.

o The remainder of the document presents the detailed specifications
for each of the classes and relationships.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119, reference
[5].

Moore, et al. Expires: Oct 1999 + 6 months [Page 5]

Internet Draft Policy Core Information Model October 1999

2. Modeling Policies

The classes comprising the Policy Core Information Model are intended
to serve as an extensible class hierarchy (through specialization) for
defining policy objects that enable application developers, network
administrators, and policy administrators to represent policies of
different types.

One way to think of a policy-controlled network is to first model the
network as a state machine and then use policy to control which state
a policy-controlled device should be in or is allowed to be in at any
given time. Given this approach, policy is applied using a set of
policy rules. Each policy rule consists of a set of conditions and a
set of actions. Policy rules may be aggregated into policy groups.
These groups may be nested, to represent a hierarchy of policies.

The set of conditions associated with a policy rule specifies when the
policy rule is applicable. The set of conditions can be expressed as
either an ORed set of ANDed sets of condition statements or an ANDed
set of ORed sets of statements. Individual condition statements can
also be negated. These combinations are termed, respectively,
Disjunctive Normal Form (DNF) and Conjunctive Normal Form (CNF) for
the conditions.

If the set of conditions associated with a policy rule evaluates to
TRUE, then a set of actions that either maintain the current state of
the object or transition the object to a new state may be executed.
For the set of actions associated with a policy rule, it is possible
to specify an order of execution, as well as an indication of whether
the order is required or merely recommended. It is also possible to
indicate that the order in which the actions are executed does not
matter.

Moore, et al. Expires: Oct 1999 + 6 months [Page 5]

Internet Draft Policy Core Information Model October 1999

Policy rules themselves can be prioritized. One common reason for
doing this is to express an overall policy that has a general case
with a few specific exceptions.

For example, a general QoS policy rule might specify that traffic
originating from members of the engineering group is to get Bronze
Service. A second policy rule might express an exception: traffic
originating from John, a specific member of the engineering group, is
to get Gold Service. Since traffic originating from John satisfies
the conditions of both policy rules, and since the actions associated
with the two rules are incompatible, a priority needs to be
established. By giving the second rule (the exception) a higher
priority than the first rule (the general case), a policy
administrator can get the desired effect: traffic originating from
John gets Gold Service, and traffic originating from all the other
members of the engineering group gets Bronze Service.

Policies can either be used in a stand-alone fashion or aggregated
into policy groups to perform more elaborate functions. Stand-alone

Moore, et al. Expires: Oct 1999 + 6 months [Page 6]

Internet Draft Policy Core Information Model October 1999

policies are called policy rules. Policy groups are aggregations of
policy rules, or aggregations of policy groups, but not both. Policy
groups can model intricate interactions between objects that have
complex interdependencies. Examples of this include a sophisticated
user logon policy that sets up application access, security, and
reconfigures network connections based on a combination of user
identity, network location, logon method and time of day. A policy
group represents a unit of reusability and manageability in that its
management is handled by an identifiable group of administrators and
its policy rules apply equally to the scope of the policy group.

Stand-alone policies are those that can be expressed in a simple
statement. They can be represented effectively in schemata or MIBs.
Examples of this are VLAN assignments, simple YES/NO QoS requests, and
IP address allocations. A specific design goal of this model is to
support both stand-alone and aggregated policies.

Policy groups and rules can be classified by their purpose and intent.
This classification is useful in querying or grouping policy rules.
It indicates whether the policy is used to motivate when or how an
action occurs, or to characterize services (that can then be used, for
example, to bind clients to network services). Describing each of
these concepts in more detail,

o Motivational Policies are solely targeted at whether or how a
policy's goal is accomplished. Configuration and Usage Policies
are specific kinds of Motivational Policies. Another example is
the scheduling of file backup based on disk write activity from 8am
to 3pm, M-F.

o Configuration Policies define the default (or generic) setup of a
managed entity (for example, a network service). Examples of

Moore, et al. Expires: Oct 1999 + 6 months [Page 6]

Internet Draft Policy Core Information Model October 1999
Configuration Policies are the setup of a network forwarding
service or a network-hosted print queue.

o Installation Policies define what can and cannot be put on a system
or component, as well as the configuration of the mechanisms that
perform the install. Installation policies typically represent
specific administrative permissions, and can also represent
dependencies between different components (e.g., to complete the
installation of component A, components B and C must be previously
successfully installed or uninstalled).

o Error and Event Policies. For example, if a device fails between
8am and 9pm, call the system administrator, otherwise call the Help
Desk.

o Usage Policies control the selection and configuration of entities
based on specific "usage" data. Configuration Policies can be
modified or simply re-applied by Usage Policies. Examples of Usage
Policies include upgrading network forwarding services after a user
is verified to be a member of a "gold" service group, or

Moore, et al. Expires: Oct 1999 + 6 months [Page 7]

Internet Draft Policy Core Information Model October 1999

reconfiguring a printer to be able to handle the next job in its
queue.

o Security Policies deal with verifying that the client is actually
who the client purports to be, permitting or denying access to
resources, selecting and applying appropriate authentication
mechanisms, and performing accounting and auditing of resources.

o Service Policies characterize network and other services (not use
them). For example, all wide-area backbone interfaces shall use a
specific type of queuing.

Service policies describe services available in the network. Usage
policies describe the particular binding of a client of the network
to services available in the network.

These categories are represented in the Policy Core Information Model
by special values defined for the PolicyKeywords property of the
abstract class Policy.

2.1. Policy Scope

Policies represent business goals and objectives. A translation must
be made between these goals and objectives and their realization in
the network. An example of this could be a Service Level Agreement
(SLA), and its objectives and metrics (Service Level Objectives, or
SLOs), that are used to specify services that the network will provide
for a given client [8]. The SLA will usually be written in high-level
business terminology. SLOs address more specific metrics in support of
the SLA. These high-level descriptions of network services and metrics
must be translated into lower-level, but also vendor- and device-
independent specifications. The Policy Core Information Model classes

Moore, et al. Expires: Oct 1999 + 6 months [Page 7]

Internet Draft Policy Core Information Model October 1999
are intended to serve as the foundation for these vendor- and device-
independent specifications.

It is envisioned that the definition of policy in this draft is
generic in nature and is applicable to Quality of Service (QoS), to
non-QoS networking applications (e.g., DHCP and IPSEC), and to non-
networking applications (e.g., backup policies, auditing access,
etc.).

2.2. Declarative versus Procedural Model

The Policy Core Information Model is declarative, not procedural.
Given that standardization efforts in policy should address policy
definitions at the Role level, the next issue is to decide on a
language framework to define policies. There are several design
considerations and trade-offs to make in this respect.

1. On one hand, we would like a policy definition language to be
reasonably human-friendly for ease of definitions and
diagnostics. On the other hand, given the diversity of devices

Moore, et al. Expires: Oct 1999 + 6 months [Page 8]

Internet Draft Policy Core Information Model October 1999

(in terms of their processing capabilities) which could act as
policy decision points, we would like to keep the language
somewhat machine-friendly, i.e., relatively simple to automate
the parsing and processing in network elements.

2. An important decision to make is the semantic style of the
language, e.g., procedural or declarative.

o The procedural approach would model network behavior that is
to be regulated through policy in terms of states and
pertinent events. In this model, policy directives are
statements that control the state transitions and thereby
regulate the network behavior. An example of state is
installing or removal of packet classification filters and
the appropriate configuration actions for traffic
conditioning. Examples of events include device boot-up,
packet arrival, etc.

o The declarative approach would simply describe the desired
network behavior in terms of certain actions that should
happen when specific conditions hold. For example, a policy
directive that states that packets matching a specific traffic
profile must be conditioned in a certain way is formulated in
terms of conditions that describe the traffic profile and
actions that describe the traffic conditioning behavior. A
policy rule in this approach is written as "if (policy
condition) then <policy action>."

The declarative approach has the benefit of simplicity, and
facilitates hiding implementation differences, making it a
suitable candidate for the policy definition language standard.

Moore, et al. Expires: Oct 1999 + 6 months [Page 8]

Internet Draft Policy Core Information Model October 1999

3. It is important to control the complexity of the language
specification trading off richness in terms of features for ease
of implementation. It is important to acknowledge the collective
lack of experience in the field of networking policies and hence
avoid the temptation of aiming for "completeness". We should
strive to facilitate definition of the common policies that
customers require today (e.g. VPN, QoS) and allow migration
paths towards supporting complex policies as customer needs and
our understanding of networking policies evolve with experience.
Specifically, in the context of the declarative style language
discussed above, it is important to avoid having full blown
predicate calculus as the language as it would render many
important problems such as consistency checking and policy
decision point algorithms intractable. It is useful to consider
a reasonably constrained language from these perspectives.

Moore, et al. Expires: Oct 1999 + 6 months [Page 9]

Internet Draft Policy Core Information Model October 1999

3. Overview of the Policy Core Information Model

The following diagram provides an overview of the five central classes
comprising the Policy Core Information Model, their relationships to
each other, and their relationships to other classes in the overall
CIM model. Note that the abstract class Policy and the two extension
classes VendorPolicyCondition and VendorPolicyAction are not shown.

NOTE: For cardinalities, "*" is an abbreviation for "0..n".

Moore, et al. Expires: Oct 1999 + 6 months [Page 9] 10]

Internet Draft Policy Core Information Model October 1999

0..n (a)
(various other CIM classes)<************************************
^ 0..n ^ 0..n *
* * *
* (b) *

+-------------------------------+ +---------------------+*
| CIM_ResourceManagerCollection | | CIM_Service <.....
+-^----------------^--------^---+ +---^-----^-------^---+ .
.* .* .* (c) *
* * *
* *************** .* .* .* .
.(a) .(b) ............. .(d) .(e) .(f)
. . ....................... . .*
. . . ......... +----v----+
. ............... . +-----------+ *
* * . | CIM_MSE |
. . . |CIM_System | *
* * ***** . +---------+
. . ..... . +--^-----^--+ ***** *
* * * * * * * * *
* * 0..n *(d)* 0..n (e)* * 0..n *(f)* 0..n * 0..n
* * +-----v---v---+ * * +-v---v-------v----+
* ****> . .....
. . . . . 1. 1. . . .
. . *.(g).* . .(h) .(i) . *.(j).*
. . +--v---v-------v-+ . . . +-v---v------------+
. ....> PolicyGroup <************** * <........ . . | PolicyRepository |
* 0..n|
. *| | w * . . | |
* +------^------+ *
. +------^---------+ . . +-----^---------^--+
* 0..n * *
. *. . . 0..1 * . 0..1 *
* * (g) * (h) * *
* 0..n * * * *
* .
. .(k) . . .(l) .(m)
. *. . . . .
. +------v------+ w * * *
* | <******************** * (i) * (j)
* . . . .
. | <................. . . .
. | PolicyRule | * *
* . . .
. | <....................... . .
. | | . .
.......> <........................ . .
*| |* (n) . . .
| | . . .
| | (k) * *
*******> <************************ * *
0..n +----------------+ . . .
| | 0..n * * * | ManagedElement | * 0..n * 0..n * . . .
| | +---------v-------v----+ * +---^---------^--+ . . .
| | .* .* . . .
| | .(o) .(p) . . .
| | . .* .* .* .
| | . +--v------v-------v----+ .
| | .......> PolicyCondition | * .
| | +----------------------+ * *+----------------------+ .
| | (l) (q) ^ * .
| <************** <.............. I * .
| | 0..n * |* . I * .
| | * 0..n .* ^ * .
| | +----v----------------------+ * .
| | | PolicyTimePeriodCondition | * .
| | +---------------------------+ *
| | *
| .
| (m) * | <************************* * (r) .
| <......................... .
| 0..n * * |* . .
| | * 0..n * .* .
| | +----------v---------+ 0..n * +----------v---------+* .
| | | PolicyAction <******* <.......
+-------------+ +--------------------+

Figure 1. Overview of the Core Policy Classes and Relationships

Moore, et al. Expires: Oct 1999 + 6 months [Page 11]

Internet Draft Policy Core Information Model October 1999

In this figure the boxes represent the classes, and the starred dotted arrows
represent the relationships. The following relationships appear:

(a) the repository jurisdiction associations ResourceManagerCollectionPolicyRule

(b) the rule jurisdiction associations

Moore, et al. Expires: Oct 1999 + 6 months [Page 10]

Internet Draft Policy Core Information Model October 1999 ResourceManagerCollectionPolicyGroup

(d) PolicyGroupInPolicyGroup ResourceManagerPolicyGroup

(e) PolicyGroupInSystem ResourceManagerPolicyRule

(f) PolicyRepositoryInPolicyRepository ResourceManagerManagedResource

(g) PolicyRuleInPolicyGroup PolicyGroupInPolicyGroup

(h) PolicyRuleInSystem PolicyGroupInSystem

(i) ConditionInPolicyRepository PolicyRuleInSystem

(j) ActionInPolicyRepository PolicyRepositoryInPolicyRepository

(k) ConditionInPolicyRule PolicyRuleInPolicyGroup

(l) PolicyRuleValidityPeriod ConditionInPolicyRepository

(m) ActionInPolicyRepository

(n) ConditionInPolicyRule

(o) ConditionSubject

(p) ConditionTarget

(q) PolicyRuleValidityPeriod

(r) ActionInPolicyRule

A relationship always connects two classes. The "two" classes may,
however, be the same class, as is the case with the
PolicyGroupInPolicyGroup relationship, which represents the recursive
containment of PolicyGroups in other PolicyGroups. The
PolicyRepositoryInPolicyRepository association is recursive in the
same way.

A relationship has associated with it cardinalities for each of the
related classes. These cardinalities indicate how many instances of
each class may be related to an instance of the other class. For
example, the PolicyRuleInPolicyGroup relationship has the cardinality
ranges "0..n"
range "*' (that is, "0..n") for both the PolicyGroup and PolicyRule
classes. These ranges are interpreted as follows:

Moore, et al. Expires: Oct 1999 + 6 months [Page 12]

Internet Draft Policy Core Information Model October 1999

o The "0..n" "*" written next to PolicyGroup indicates that a PolicyRule may
be related to no PolicyGroups, to one PolicyGroup, or to more than
one PolicyGroup via the PolicyGroupInPolicyGroup relationship. In
other words, a PolicyRule may be contained in no PolicyGroups, in
one PolicyGroups, or in more than one PolicyGroup.

o The "0..n" "*" written next to PolicyRule indicates that a PolicyGroup may
be related to no PolicyRules, to one PolicyRule, or to more than
one PolicyRule via the PolicyGroupInPolicyGroup relationship. In
other words, a PolicyGroup may contain no PolicyRules, one
PolicyRule, or more than one PolicyRule.

The "w" written next to the PolicyGroupInSystem and PolicyRuleInSystem
indicates that these are what CIM terms "aggregations with weak
references", or more briefly, "weak aggregations." A weak
aggregation is simply an indication of a naming scope. Thus these two

Moore, et al. Expires: Oct 1999 + 6 months [Page 11]

Internet Draft Policy Core Information Model October 1999
aggregations indicate that an instance of a PolicyGroup or PolicyRule
is named within the scope of a System object. A weak aggregation
implicitly has the cardinalities 0..n at the "w" end, and cardinality 1..1 at the end opposite end. the 'w'.

The relationships shown in Figure 1 are discussed in more detail in
Section 7.

4. Inheritance Hierarchies for the Core Policy Classes and Relationships

The following diagram illustrates the inheritance hierarchy for the
core policy classes:

Top

Moore, et al. Expires: Oct 1999 + 6 months [Page 13]

Internet Draft Policy Core Information Model October 1999

Figure 2. Inheritance Hierarchy for the Core Policy Classes

The System and AdminDomain classes are defined in the current version
of the CIM model [7]. They [7], and the ManagedElement and Collection classes
are not discussed in detail in this
document. currently being defined by the DMTF's User WG. These classes are
not discussed in detail in this document.

In CIM, relationships are also modeled as classes. For the Policy
Core Information Model, the inheritance hierarchy for the
relationships has has, with one exception, only a single level:

Moore, et al. Expires: Oct 1999 + 6 months [Page 12] 14]

Internet Draft Policy Core Information Model October 1999

Top

Figure 3. Inheritance Hierarchy for the Core Policy Relationships

Near the bottom of Figure 3 there are three groups of four
relationships, representing jurisdictions. These relationships are
the vehicle for tying instances of the policy classes to instances

5. Details of
other classes that represent the elements Model

The following subsections discuss several specific issues related to which
the policies are to CIM Core Policy model.

Moore, et al. Expires: Oct 1999 + 6 months [Page 13] 15]

Internet Draft Policy Core Information Model October 1999

be applied. There are three relationships with each of four high-
level CIM classes: Setting, ManagedSystemElement (MSE),
ResponsibleEntity, and Collection. These relationships indicate that
a PolicyGroup, a PolicyRule, or (the objects contained in) a
PolicyRepository applies to a Setting, an MSE, a ResponsibleEntity, or
a Collection.

5. Details of the Model

The following subsections discuss several specific issues related to
the CIM Core Policy model.

5.1. Reusable versus Rule-Specific Conditions and Actions

Policy conditions and policy actions can be partitioned into two
groups: ones associated with a single policy rule, and ones that are
reusable, in the sense that they may be associated with more than one
policy rule. Conditions and actions in the first group are termed
"rule-specific" conditions and actions; those in the second group are
characterized as "reusable".

It is important to understand that the difference between a rule-
specific condition or action and a reusable one is based on the intent
of the policy administrator for the condition or action, rather than
on the current associations in which the condition or action
participates. Thus a reusable condition or action (that is, one that
a policy administrator has created to be reusable) may at some point
in time be associated with exactly one policy rule, without thereby
becoming rule-specific.

There is no inherent difference between a rule-specific condition or
action and a reusable one. There are, however, differences in how
they are treated in a policy repository. For example, it's natural to
make the access permissions for a rule-specific condition or action
identical to those for the rule itself. It's also natural for a rule-
specific condition or action to be removed from the policy repository
at the same time the rule is. With reusable conditions and actions,
on the other hand, access permissions and existence criteria must be
expressible without reference to a policy rule.

The preceding paragraph does not contain an exhaustive list of the
ways in which reusable and rule-specific conditions should be treated
differently. Its purpose is merely to justify making a semantic
distinction between rule-specific and reusable, and then reflecting
this distinction in the policy repository itself.

Another issue is highlighted by reusable and rule-specific policy
conditions and policy actions: the lack of a capability in CIM for
expressing complex constraints involving multiple associations.
Taking PolicyCondition as an example, there are two aggregations to
look at. ConditionInPolicyRule has the cardinality [0..n] [* ] at both

Moore, et al. Expires: Oct 1999 + 6 months [Page 14]

Internet Draft Policy Core Information Model October 1999
ends, and ConditionInPolicyRepository has the cardinality [0..n] at
the PolicyCondition end, and [0..1] at the PolicyRepository end.

Globally, these cardinalities are correct. However, there's more to
the story, which only becomes clear if we examine the cardinalities
separately for the two cases of a rule-specific PolicyCondition and a
reusable one.

For a rule-specific PolicyCondition, the cardinality of
ConditionInPolicyRule at the PolicyRule end is [1..1], rather than
[0..n], since the condition is unique to one policy rule. And the
cardinality of ConditionInPolicyRepository at the PolicyRepository end
is [0..0].

Moore, et al. Expires: Oct 1999 + 6 months [Page 16]

Internet Draft Policy Core Information Model October 1999

For a reusable PolicyCondition, however, the cardinality of
ConditionInPolicyRepository at the PolicyRepository end is [1..1], and
that of the ConditionInPolicyRule at the PolicyRule end is [0..n].
This last point is important: a reusable PolicyCondition may be
associated with 0, 1, or more than 1 PolicyRules, via exactly the same
association ConditionInPolicyRule that supports manual propagation of
key values (from a single PolicyRule) in the case of a rule-specific
PolicyCondition. But the reusable PolicyCondition gets its key values
via a different association ConditionInPolicyRepository.

Currently the only way to document constraints of this type in CIM is
textually. People in the DMTF are beginning to think about how CIM
might be extended to accommodate more formal methods for documenting
complex constraints.

5.2. Naming in the Policy Core Information Model

While the CommonName property is present in the abstract superclass
Policy, Roles and is thus available in all Resource Managers

The concept of its instantiable subclasses,
the Policy Core Information Model does not use this property for
naming instances. (The directory attribute commonName role is central to which the
CommonName property maps is, however, available as one design of the options
for instance naming in the entire Policy Framework LDAP Core Schema [9].)
Framework. (For more on roles, see reference [11].) The following subsections discuss how naming idea behind
roles is handled in each of the
instantiable classes in the Policy Core Information Model.

5.2.1. Naming Instances of PolicyGroup a simple one. Rather than configuring, and PolicyRule

A policy group always exists in some context. In then later having
to update the Policy Core
Information Model, this contextual character configuration of, hundreds or thousands (or more) of
resources in a policy group is
captured by the weak aggregation PolicyGroupInSystem between a
PolicyGroup and a System. When a CIM relationship is specified as
"weak", this is network, a statement about naming scopes: an instance of the
class at the weak end of the relationship is named within the scope of
an instance of the class at the other end of the relationship. This
is accomplished by propagation of keys from the instance of the
scoping class policy administrator assigns each resource
to the instance of the weak class. Thus the weak class
has, via propagation, all the keys from the scoping class, and it also

Moore, et al. Expires: Oct 1999 + 6 months [Page 15]

Internet Draft Policy Core Information Model October 1999

has one or more additional keys (unless roles, and then specifies the weak class is abstract) policies for distinguishing instances each of the weak class named within the scope
these roles. The Policy Framework is then responsible for configuring
each of the same instance of resources associated with a role in such a way that it
behaves according to the scoping class.

A policy rule policies specified for that role. When
network behavior must also exist in some context. In be changed, the Policy Core
Information Model, this contextual character of a policy rule is
captured by administrator can perform
a single update to the weak association PolicyRuleInSystem between policy for a
PolicyRule role, and a System.

5.2.2. Naming Instances of PolicyCondition and Its Subclasses

As indicated above the Policy Framework
will insure that the necessary configuration updates are performed on
all the resources playing that role.

+---------------------------+
| ResourceManagerCollection |
| RMType = {"FR"} |
+---------------------------+

+----------------------+ +----------------------+
| Router 1 | | Router 2 |
| | | |
| +-----------------+ | | +-----------------+ |
| | ResourceManager | | | | ResourceManager | |
| | RMType = {"FR"}| | | | RMType = {"FR"}| |
| +-----------------+ | | +-----------------+ |
| FR-1a FR-1b FR 1-c | | FR-2a FR-2b FR 2-c |
+----------------------+ +----------------------+

Figure 4. The ResourceManagerCollection Object

Roles are represented in Section 5.1, the single Core Model by the class PolicyCondition
ResourceManagerCollection. As Figure 4 illustrates, there is
used a three-
level hierarchy:

Moore, et al. Expires: Oct 1999 + 6 months [Page 17]

Internet Draft Policy Core Information Model October 1999

o A ResourceManagerCollection is an abstraction that represents a set
of individual resource managers within a policy domain.

o A resource manager is a component that manages access to represent both reusable and rule-specific policy conditions. use of
a set of resources.

o The distinction between resources themselves are under the two types control of policy conditions lies in a resource
manager.

In Figure 4, the
relationships that different instances of PolicyCondition participate
in, and resources in how the different instances question are named. Conceptually, a
reusable policy condition resides in individual frame relay
interfaces. Each router has a policy repository, and is named
within resource manager component that manages
all of its frame relay interfaces. Finally, the scope model contains an
abstraction representing the collection of that repository. On all the other hand, a rule-
specific policy condition is, as frame relay
interfaces in all the name suggests, named routers within the
scope of the single policy rule domain. This
abstraction corresponds to which it is related.

Naming scopes are represented in CIM by means of weak associations.
However, CIM has the restriction that role "Frame Relay Interface".

The Core Model contains a given class can only
participate at the weak end number of relationships for navigating among
the elements shown in Figure 4:

o Associations between PolicyGroup and PolicyRule on the one weak association. Another way of
expressing hand,
and ResourceManagerCollection on the restriction is other, which tie policies to say that all instances of a given
class must be named within the scope of
roles.

o Alternatively, associations between PolicyGroup and PolicyRule on
the same class (or in one hand, and ResourceManager on the
scope of no class at all, if they are named other, which bypass roles,
and tie policies directly in the global CIM
name space). Clearly, then, the CIM naming architecture is not
capable of expressing what we need it to express: that a given
PolicyCondition instance is named EITHER in the scope of individual resource managers.

o A MemberResourceManager aggregation, which ties a policy rule
(if it is
ResourceManagerCollection to its constituent resource managers.

o A ResourceManagerManagedResource association to tie a rule-specific condition) OR in resource
manager to the scope of a policy
repository (if individual resources that it is a reusable one).

To work around manages.

Once this restriction (which may be removed in a future
version set of CIM), relationships has been set up, it is necessary possible for the
policy administrator to "simulate" weak associations
between PolicyCondition and PolicyRule and between PolicyCondition and
PolicyRepository, through a technique we'll call manual key
propagation.

Figure 4 illustrates how manual propagation works in influence the case behavior of
PolicyCondition; note that only the key properties are shown for each all of these frame
relay interfaces by updating a single policy object.

5.3. Naming in the classes. In Policy Core Information Model

While the figure, CommonName property is present in the line composed of 'I's indicates
class inheritance, abstract superclass
Policy, and is thus available in all of its instantiable subclasses,
the Policy Core Information Model does not use this property for
naming instances. (The directory attribute commonName to which the
CommonName property maps is, however, available as one composed of 'P's indicates (true) key
propagation via the weak aggregation PolicyRuleInSystem, and options
for instance naming in the ones
composed Policy Framework LDAP Core Schema [9].)
The following subsections discuss how naming is handled in each of 'M's indicate manual key propagation. the
instantiable classes in the Policy Core Information Model.

5.3.1. Role of the CreationClassName Property in Naming

To provide for more flexibility in instance naming, CIM makes use of a
property called CreationClassName. The idea of CreationClassName is

Moore, et al. Expires: Oct 1999 + 6 months [Page 16] 18]

Internet Draft Policy Core Information Model October 1999

(*) Note that as part of this manual propagation, the zero-length
string ("") is assigned

to the PolicyRuleName property.

Figure 4. Manual Key Propagation for Naming PolicyConditions

Looking at Figure 4, we see provide another dimension that two key properties
SystemCreationClassName and Name are defined can be used to avoid naming
collisions, in the System Class, and
inherited by its subclasses AdminDomain and PolicyRepository. Since
PolicyRule is weak specific case of instances belonging to System, these two keys are propagated to it; it
also has its own key PolicyRuleName. The "dot" notation (for example,
"System.Name") indicates that SystemCreationClassName and Name are
propagated keys
different subclasses of the class PolicyRule.

The manual propagation a common instantiable superclass. An example
will illustrate how CreationClassName works.

Suppose we have instances of keys from PolicyRule to PolicyCondition
involves copying the values two different subclasses of PolicyRule's three key properties into

Moore, et al. Expires: Oct 1999 + 6 months [Page 17]

Internet Draft Policy Core Information Model October 1999

three similarly named key properties in PolicyCondition. Note,
though,
PolicyCondition, FrameRelayPolicyCondition and BgpPolicyCondition, and
that the "dot" notation is absent: PolicyCondition's second
key property is "SystemName", not "System.Name".

The manual propagation of keys from PolicyRepository these instances apply to
PolicyCondition works in exactly the same way context. If we had only the
single key property PolicyConditionName available for distinguishing
the first two key
properties. Since, however, PolicyRepository doesn't have
PolicyRuleName as instances, then a third key property, there is no value to copy into collision would result from naming both of
the PolicyRuleName key property in PolicyCondition. A special value, instances with the zero-length string (""), is assigned key value PCName = "PC-1". Thus policy
administrators from widely different disciplines would have to PolicyRuleName in this
case, indicating that
coordinate their naming of PolicyConditions for this instance context.

With CreationClassName, collisions of PolicyCondition is not named
within this type are eliminated,
without requiring coordination among the scope of any particular policy rule. This matches the
semantics administrators. The
two instances would now be distinguishable because of a reusable policy condition, which exists and the fact that
their CreationClassNames would have different values. One instance is
now identified independent of any associations it might have with specific
policy rules.

5.2.3. the two keys

CreationClassName = "FrameRelayPolicyCondition" + PCName = "PC-1",

while the other is identified with

CreationClassName = "BgpPolicyCondition" + PCName = "PC-1".

Each of the instantiable classes in the Core Model includes the
CreationClassName property as a key in addition to its own class-
speific key property.

5.3.2. Naming Instances of PolicyAction PolicyGroup and Its Subclasses

From PolicyRule

A policy group always exists in some context. In the point of view Policy Core
Information Model, this contextual character of naming, the PolicyAction class and its
subclasses work exactly like a policy group is
captured by the PolicyCondition class weak aggregation PolicyGroupInSystem between a
PolicyGroup and its
subclasses. See Section 5.2.2 for details.

5.3. CIM Data Types

The following a System. When a CIM data types are used in relationship is specified as
"weak", this is a statement about naming scopes: an instance of the
class definitions that
follow in Sections 6 and 7:

o uint8 unsigned 8-bit integer

o uint16 unsigned 16-bit integer

o boolean Boolean

o string UCS-2 string.

In addition, at the association classes in Section 7 use weak end of the following
type:

o <classname> ref strongly typed reference.

The notation "octetString" relationship is also used as named within the data type for scope of
an instance of the two
properties Constraint (in VendorPolicyCondition) and ActionData (in
VendorPolicyAction). See class at the sections describing these two properties
for an explanation other end of what this notation indicates.

6. Class Definitions

There are a significant number the relationship. This
is accomplished by propagation of differences between CIM and LDAP keys from the instance of the
scoping class specifications. The ones that are relevant to the abbreviated
class specifications in instance of the weak class. Thus the weak class
has, via propagation, all the keys from the scoping class, and it also
has one or more additional keys (unless the weak class is abstract)
for distinguishing instances of the weak class named within the scope
of the same instance of the scoping class.

A policy rule must also exist in some context. In the Policy Core
Information Model, this document are contextual character of a policy rule is
captured by the following: weak association PolicyRuleInSystem between a
PolicyRule and a System.

Moore, et al. Expires: Oct 1999 + 6 months [Page 18] 19]

Internet Draft Policy Core Information Model October 1999

o Instead

5.3.3. Naming Instances of LDAP's three class types (abstract, auxiliary,
structural), CIM has only two: abstract PolicyCondition and instantiable. The
type of a CIM class is Its Subclasses

As indicated by above in Section 5.1, the Boolean qualifier ABSTRACT.

o CIM uses single class PolicyCondition is
used to represent both reusable and rule-specific policy conditions.
The distinction between the term "property" for what LDAP terms an "attribute".

o CIM uses two types of policy conditions lies in the array notation "[ ]" to indicate
relationships that a property is
multi-valued. As is the case with LDAP, multi-valued properties different instances of PolicyCondition participate
in, and in
CIM how the different instances are unordered.

o There is no distinction named. Conceptually, a
reusable policy condition resides in a CIM class between mandatory policy repository, and
optional properties. Aside from is named
within the key properties (designated for
naming instances scope of that repository. On the class), all properties are optional.

o CIM classes and properties are identified by name, not by OID.

o In LDAP, attribute definitions are global, and the same attribute
may appear in multiple classes. In CIM, other hand, a property is defined rule-
specific policy condition is, as the name suggests, named within the
scope of a single class definition. The property may be
inherited into subclasses of the class in single policy rule to which it is defined, but
otherwise it cannot appear related.

Naming scopes are represented in other classes. One side effect CIM by means of
this difference is that weak associations.
However, CIM property names tend has the restriction that a given class can only
participate at the weak end of one weak association. Another way of
expressing the restriction is to say that all instances of a given
class must be much shorter
than LDAP attribute names, since they are implicitly scoped by named within the
name scope of the same class (or in which the
scope of no class at all, if they are defined.

For named directly in the complete definition of global CIM
name space). Clearly, then, the CIM specification language, see
reference [7].

6.1. The Abstract Class "Policy"

The abstract class Policy collects five properties naming architecture is not
capable of expressing what we need it to express: that may be
included a given
PolicyCondition instance is named EITHER in instances of any of the Core Policy classes (or their
subclasses).

The class definition scope of a policy rule
(if it is as follows:

NAME Policy
DESCRIPTION An abstract class with four properties for
describing a policy-related instance.
DERIVED FROM Top
ABSTRACT TRUE
PROPERTIES CommonName (CN)
Caption
Description
PolicyKeywords[ ]

6.1.1. The Property "CommonName (CN)"

The CN, or CommonName, property corresponds to rule-specific condition) OR in the X.500 attribute
commonName (cn). In X.500 this property specifies one or more user-
friendly names (typically only one name) by which an object scope of a policy
repository (if it is
commonly known, names that conform a reusable one).

To work around this restriction (which may be removed in a future
version of CIM), it is necessary to "simulate" weak associations
between PolicyCondition and PolicyRule and between PolicyCondition and
PolicyRepository, through a technique we'll call manual key
propagation.

Figure 5 illustrates how manual propagation works in the naming conventions case of
PolicyCondition; note that only the key properties are shown for each
of the classes. In the figure, the line composed of 'I's indicates
class inheritance, the one composed of 'P's indicates (true) key
propagation via the weak aggregation PolicyRuleInSystem, and the ones
composed of 'M's indicate manual key propagation.

Moore, et al. Expires: Oct 1999 + 6 months [Page 19] 20]

Internet Draft Policy Core Information Model October 1999

country or culture with which

(*) Note that as part of this manual propagation, the object special string
"No Rule" is associated. In the CIM
model, however, assigned to the CommonName property is single-valued.

NAME CN
DESCRIPTION A user-friendly name of a policy-related object.
SYNTAX string

6.1.2. The Property "Caption"

This property provides a one-line description of a policy-related CIM
object.

NAME Caption
DESCRIPTION A one-line description of this policy-related
object.
SYNTAX string

6.1.3. The Property "Description"

This property provides a longer description than PolicyRuleCreationClassName and
PolicyRuleName properties.

Figure 5. Manual Key Propagation for Naming PolicyConditions

Looking at Figure 5, we see that provided by two key properties
SystemCreationClassName and Name are defined in the
caption property.

NAME Description
DESCRIPTION A long description of this policy-related object.
SYNTAX string

6.1.4. System Class, and
inherited by its subclasses AdminDomain and PolicyRepository. Since
PolicyRule is weak to System, these two keys are propagated to it; it
also has its own keys CreationClassName and PolicyRuleName. The Multi-valued Property "PolicyKeywords"

This property provides a set of one or more keywords "dot"
notation (for example, "System.Name") indicates that a policy
administrator may use to assist in characterizing or categorizing a
policy object. Keywords

Moore, et al. Expires: Oct 1999 + 6 months [Page 21]

Internet Draft Policy Core Information Model October 1999

SystemCreationClassName and Name are propagated keys of one the class
PolicyRule.

The manual propagation of two types:

o Keywords defined in this document, or keys from PolicyRule to PolicyCondition
involves copying the values of PolicyRule's four key properties into
four similarly named key properties in documents PolicyCondition. Note, though,
that define
subclasses of the classes defined "dot" notation is absent: PolicyCondition's second key
property is "SystemName", not "System.Name".

The manual propagation of keys from PolicyRepository to
PolicyCondition works in this document. These keywords
provide a vendor-independent, installation-independent exactly the same way of
characterizing policy objects.

o Installation-dependent keywords for characterizing policy objects.
Examples include "Engineering", "Billing", the first two key
properties. Since, however, PolicyRepository doesn't have
[PolicyRule]CreationClassName and "Review in December
1999".

This document defines PolicyRuleName as its third and
fourth key properties, there are no values to copy into the following keywords: "UNKNOWN",
"CONFIGURATION", "USAGE", "SECURITY", "SERVICE", "MOTIVATIONAL",
"INSTALLATION",
PolicyRuleCreationClassName and "EVENT". These concepts were defined earlier PolicyRuleName key properties in
Section 2.

One additional keyword
PolicyCondition. A special value, "No Rule", is defined: "POLICY". The role assigned to both of
these properties in this
keyword is to identify policy-related instances case, indicating that would this instance of
PolicyCondition is not
otherwise be identifiable as being related to policy.

Documents that define subclasses named within the scope of any particular policy
rule. This matches the Policy Core Information Model
classes SHOULD define additional keywords to characterize instances semantics of a reusable policy condition,
which exists and is identified independent of any associations it
might have with specific policy rules.

5.3.4. Naming Instances of PolicyAction and Its Subclasses

From the point of view of naming, the PolicyAction class and its
subclasses work exactly like the PolicyCondition class and its
subclasses. See Section 5.3.3 for details.

5.3.5. Naming Instances of PolicyRepository and
ResourceManagerCollection

Instances of these two classes are named directly in the global CIM
name space, using the CreationClassName property and a class-unique
key property (PolicyRepositoryName and ResourceManagerCollectionName,
respectively).

5.4. CIM Data Types

The following CIM data types are used in the class definitions that
follow in Sections 6 and 7:

o uint8 unsigned 8-bit integer

o uint16 unsigned 16-bit integer

o boolean Boolean

o string UCS-2 string.

Moore, et al. Expires: Oct 1999 + 6 months [Page 20] 22]

Internet Draft Policy Core Information Model October 1999

these subclasses. By convention, keywords defined in conjunction with
class definitions are in uppercase. Installation-defined keywords can
be

In addition, the association classes in any case. Section 7 use the following
type:

o <classname> ref strongly typed reference.

The property definition notation "octetString" is also used as follows:

NAME PolicyKeywords
DESCRIPTION A set of keywords the data type for characterizing /categorizing
policy objects.
SYNTAX string

6.2. The the two
properties Constraint (in VendorPolicyCondition) and ActionData (in
VendorPolicyAction). See the sections describing these two properties
for an explanation of what this notation indicates.

6. Class "PolicyGroup"

This class is Definitions

There are a generalized aggregation container. It enables either
PolicyRules or PolicyGroups, but not both, significant number of differences between CIM and LDAP
class specifications. The ones that are relevant to be aggregated the abbreviated
class specifications in a
single container. Loops, including this document are the degenerate case following:

o Instead of LDAP's three class types (abstract, auxiliary,
structural), CIM has only two: abstract and instantiable. The
type of a
PolicyGroup CIM class is indicated by the Boolean qualifier ABSTRACT.

o CIM uses the term "property" for what LDAP terms an "attribute".

o CIM uses the array notation "[ ]" to indicate that contains itself, are not allowed when PolicyGroups
contain other PolicyGroups.

PolicyGroups and their nesting capabilities a property is
multi-valued. As is the case with LDAP, multi-valued properties in
CIM are shown unordered.

o There is no distinction in Figure 5
below. Note that a PolicyGroup can nest other PolicyGroups, CIM class between mandatory and there
is no restriction on
optional properties. Aside from the depth key properties (designated for
naming instances of the nesting in sibling PolicyGroups.

+---------------------------------------------------+
| PolicyGroup |
| |
| +--------------------+ +-----------------+ |
| | PolicyGroup A | | PolicyGroup X | |
| | | | | |
| | +----------------+ | ooo | | |
| | | PolicyGroup A1 | | | | |
| | +----------------+ | | | |
| +--------------------+ +-----------------+ |
+---------------------------------------------------+

Figure 5. Overview of the PolicyGroup class

As a simple example, think of class), all properties are optional.

o CIM classes and properties are identified by name, not by OID.

o In LDAP, attribute definitions are global, and the highest level PolicyGroup shown same attribute
may appear in
Figure 5 above as multiple classes. In CIM, a logon policy for US employees property is defined
within the scope of a company. This
PolicyGroup single class definition. The property may be called USEmployeeLogonPolicy, and may aggregate
several PolicyGroups that provide specialized rules per location.
Hence, PolicyGroup A in Figure 5 above may define logon rules for
employees on the West Coast, while another PolicyGroup might define
logon rules for the Midwest (e.g., PolicyGroup X), and so forth.

Note also that
inherited into subclasses of the depth class in which it is defined, but
otherwise it cannot appear in other classes. One side effect of each PolicyGroup does not need
this difference is that CIM property names tend to be much shorter
than LDAP attribute names, since they are implicitly scoped by the
same. Thus, the WestCoast PolicyGroup might have several additional
layers of PolicyGroups defined for any of several reasons (different
locales, number
name of subnets, etc.). The PolicyRules are therefore
contained at n levels from the USEmployeeLogonPolicyGroup. Compare
this to the Midwest PolicyGroup (PolicyGroup X), class in which might directly
contain PolicyRules. they are defined.

For the complete definition of the CIM specification language, see
reference [7].

6.1. The Abstract Class "Policy"

The abstract class Policy collects several properties that may be
included in instances of any of the Core Policy classes (or their
subclasses).

Moore, et al. Expires: Oct 1999 + 6 months [Page 21] 23]

Internet Draft Policy Core Information Model October 1999

The

Since the class from which Policy is derived, ManagedElement, is still
under development in CIM, its definition is not readily available.
Thus the properties that Policy inherits from ManagedElement are
repeated here for PolicyGroup completeness.

The class definition is as follows:

NAME PolicyGroup Policy
DESCRIPTION A container An abstract class with four properties for either a set of related PolicyRules
or
describing a set of related PolicyGroups. policy-related instance.
DERIVED FROM Policy ManagedElement
ABSTRACT FALSE TRUE
PROPERTIES System.CreationClassName[key]
System.Name[key]
PolicyGroupName[key]

6.2.1. CommonName (CN)
PolicyKeywords[ ]
// Caption (inherited)
// Description (inherited)

6.1.1. The Propagated Key Property "System.CreationClassName"

This "CommonName (CN)"

The CN, or CommonName, property represents the name of the CIM class corresponds to which the System
object providing the naming scope for this instance of PolicyGroup
belongs. Reference [7] defines X.500 attribute
commonName (cn). In X.500 this property as follows:

[Key, MaxLen (256), Description (
"CreationClassName indicates specifies one or more user-
friendly names (typically only one name) by which an object is
commonly known, names that conform to the name naming conventions of the class
country or culture with which the "
"subclass used in object is associated. In the creation of an instance. When used "
"with CIM
model, however, the other key properties of this class, this CommonName property "
"allows all instances is single-valued.

NAME CN
DESCRIPTION A user-friendly name of this class and its subclasses to "
"be uniquely identified.") ] a policy-related object.
SYNTAX string CreationClassName;

Class names in CIM are limited to alphabetic and numeric characters
plus the underscore.

6.2.2.

6.1.2. The Propagated Key Multi-valued Property "System.Name" "PolicyKeywords"

This property represents the name provides a set of the particular System object
providing the naming scope for this instance one or more keywords that a policy
administrator may use to assist in characterizing or categorizing a
policy object. Keywords are of PolicyGroup.
Reference [7] defines this property as follows:

[Key, MaxLen (256), Override ("Name"), Description (
"The inherited Name serves as key one of a System instance two types:

o Keywords defined in "
"an enterprise environment.") ]
string Name;

The value 256 this document, or in MaxLen refers to the maximum number documents that define
subclasses of characters the classes defined in this document. These keywords
provide a System Name, rather than to the maximum number vendor-independent, installation-independent way of bytes.

6.2.3. The Key Property "PolicyGroupName"

This property provides a user-friendly name
characterizing policy objects.

o Installation-dependent keywords for a characterizing policy group, objects.
Examples include "Engineering", "Billing", and is
normally what will be displayed to the end-user as "Review in December
1999".

This document defines the instance name.
It is following keywords: "UNKNOWN",
"CONFIGURATION", "USAGE", "SECURITY", "SERVICE", "MOTIVATIONAL",
"INSTALLATION", and "EVENT". These concepts were defined as follows:

NAME PolicyGroupName
DESCRIPTION The user-friendly name of this policy group.
SYNTAX string
QUALIFIER key earlier in
Section 2.

Moore, et al. Expires: Oct 1999 + 6 months [Page 22] 24]

Internet Draft Policy Core Information Model October 1999

6.3.

One additional keyword is defined: "POLICY". The Class "PolicyRule"

This class represents the "If Condition then Action" semantics
associated with a policy. A PolicyRule condition, in the most general
sense, role of this
keyword is represented as either an ORed set of ANDed conditions
(Disjunctive Normal Form, or DNF) or an ANDed set of ORed conditions
(Conjunctive Normal Form, or CNF). Individual conditions may either be
negated (NOT C) or unnegated (C). The actions specified by a
PolicyRule are to identify policy-related instances that would not
otherwise be performed if and only if the PolicyRule condition
(whether it is represented in DNF or CNF) evaluates identifiable as being related to TRUE.

The conditions and actions associated with a policy rule are modeled,
respectively, with policy.

Documents that define subclasses of the Policy Core Information Model
classes PolicyCondition and
PolicyAction. These condition and action objects are tied SHOULD define additional keywords to characterize instances of PolicyRule by the ConditionInPolicyRule and
ActionInPolicyRule aggregations.

As illustrated above
these subclasses. By convention, keywords defined in Section 3, a policy rule may also be
associated conjunction with one or more policy time periods, indicating the
schedule according to which the policy rule
class definitions are in uppercase. Installation-defined keywords can
be in any case.

The property definition is active and inactive.
In as follows:

NAME PolicyKeywords
DESCRIPTION A set of keywords for characterizing /categorizing
policy objects.
SYNTAX string

6.1.3. The Property "Caption" (Inherited from ManagedElement)

This property provides a one-line description of a policy-related CIM
object.

NAME Caption
DESCRIPTION A one-line description of this case it is the PolicyRuleValidityPeriod aggregation that policy-related
object.
SYNTAX string

6.1.4. The Property "Description" (Inherited from ManagedElement)

This property provides a longer description than that provided by the linkage.
caption property.

NAME Description
DESCRIPTION A policy rule long description of this policy-related object.
SYNTAX string

6.2. The Class "PolicyGroup"

This class is illustrated conceptually in a generalized aggregation container. It enables either
PolicyRules or PolicyGroups, but not both, to be aggregated in a
single container. Loops, including the degenerate case of a
PolicyGroup that contains itself, are not allowed when PolicyGroups
contain other PolicyGroups.

PolicyGroups and their nesting capabilities are shown in Figure 6. 6
below.

+------------------------------------------------+ Note that a PolicyGroup can nest other PolicyGroups, and there
is no restriction on the depth of the nesting in sibling PolicyGroups.

Moore, et al. Expires: Oct 1999 + 6 months [Page 25]

Internet Draft Policy Core Information Model October 1999

+---------------------------------------------------+
| PolicyRule PolicyGroup |
| |
| +--------------------+ +-----------------+ |
| | PolicyCondition(s) PolicyGroup A | | PolicyAction(s) PolicyGroup X | |
| +--------------------+ +-----------------+ | | | | +------------------------------+ |
| | PolicyTimePeriodCondition(s) +----------------+ | ooo | | +------------------------------+ |
+------------------------------------------------+
| | | PolicyGroup A1 | | | | |
| | +----------------+ | | | |
| +--------------------+ +-----------------+ |
+---------------------------------------------------+

Figure 6. Overview of the PolicyRule Class

The PolicyRule PolicyGroup class uses the property ConditionListType, to indicate
whether

As a simple example, think of the conditions highest level PolicyGroup shown in
Figure 6 above as a logon policy for the rule are US employees of a company. This
PolicyGroup may be called USEmployeeLogonPolicy, and may aggregate
several PolicyGroups that provide specialized rules per location.
Hence, PolicyGroup A in DNF or CNF. The
ConditionInPolicyRule aggregation contains two additional properties
to complete Figure 6 above may define logon rules for
employees on the representation of West Coast, while another PolicyGroup might define
logon rules for the rule's conditional expression.
The first Midwest (e.g., PolicyGroup X), and so forth.

Note also that the depth of these properties is an integer each PolicyGroup does not need to partition be the
referenced conditions into one or more sets, and
same. Thus, the second is a
Boolean WestCoast PolicyGroup might have several additional
layers of PolicyGroups defined for any of several reasons (different
locales, number of subnets, etc.). The PolicyRules are therefore
contained at n levels from the USEmployeeLogonPolicyGroup. Compare
this to indicate whether a referenced condition the Midwest PolicyGroup (PolicyGroup X), which might directly
contain PolicyRules.

The class definition for PolicyGroup is negated. An
example shows how ConditionListType and these two additional
properties provide as follows:

NAME PolicyGroup
DESCRIPTION A container for either a unique representation set of related PolicyRules
or a set of conditions in
either DNF related PolicyGroups.
DERIVED FROM Policy
ABSTRACT FALSE
PROPERTIES System.CreationClassName[key]
System.Name[key]
CreationClassName[key]
PolicyGroupName[key]

6.2.1. The Propagated Key Property "System.CreationClassName"

This property represents the name of the CIM class to which the System
object providing the naming scope for this instance of PolicyGroup
belongs. Reference [7] defines this property as follows:

[Key, MaxLen (256), Description (
"CreationClassName indicates the name of the class or CNF. the "
"subclass used in the creation of an instance. When used "
"with the other key properties of this class, this property "

Moore, et al. Expires: Oct 1999 + 6 months [Page 23] 26]

Internet Draft Policy Core Information Model October 1999

Suppose we have a PolicyRule that aggregates five PolicyConditions C1
through C5, with the following values

"allows all instances of this class and its subclasses to "
"be uniquely identified.") ]
string CreationClassName;

Class names in CIM are limited to alphabetic and numeric characters
plus the properties underscore.

6.2.2. The Propagated Key Property "System.Name"

This property represents the name of the five
ConditionInPolicyRule relationships:

C1: GroupNumber = 1, ConditionNegated = FALSE
C2: GroupNumber = 1, ConditionNegated = TRUE
C3: GroupNumber = 1, ConditionNegated = FALSE
C4: GroupNumber = 2, ConditionNegated = FALSE
C5: GroupNumber = 2, ConditionNegated = FALSE

If ConditionListType = DNF, then particular System object
providing the overall condition naming scope for this instance of PolicyGroup.
Reference [7] defines this property as follows:

[Key, MaxLen (256), Override ("Name"), Description (
"The inherited Name serves as key of a System instance in "
"an enterprise environment.") ]
string Name;

The value 256 in MaxLen refers to the
PolicyRule is:

(C1 AND (NOT C2) AND C3) OR (C4 AND C5)

On maximum number of characters in
a System Name, rather than to the other hand, if ConditionListType = CNF, then maximum number of bytes.

6.2.3. The Key Property "CreationClassName"

This property identifies the overall
condition for class or subclass used in the PolicyRule is:

(C1 OR (NOT C2) OR C3) AND (C4 OR C5)

In both cases, there is an unambiguous specification creation of
this instance.

NAME CreationClassName
DESCRIPTION The name of the overall
condition that class or subclass used in the
creation of this instance.
SYNTAX string[MaxLen 256]
QUALIFIER key

6.2.4. The Key Property "PolicyGroupName"

This property provides a user-friendly name for a policy group, and is tested to determine whether
normally what will be displayed to perform the actions
associated with end-user as the PolicyRule.

The class definition instance name.
It is defined as follows:

NAME PolicyRule PolicyGroupName
DESCRIPTION The central user-friendly name of this policy group.
SYNTAX string
QUALIFIER key

6.3. The Class "PolicyRule"

This class for representing represents the "If Condition then Action" semantics
associated with a
policy rule.
DERIVED FROM Policy
ABSTRACT FALSE
PROPERTIES System.CreationClassName[key]
System.Name[key]
PolicyRuleName[key]
Enabled
ConditionListType
RuleUsage
Priority
Mandatory
SequencedActions

6.3.1. The Propagated Key Property "System.CreationClassName"

System.CreationClassName works policy. A PolicyRule condition, in the same way here most general
sense, is represented as it does for the
class PolicyGroup. See Section 6.2.1 for details.

6.3.2. either an ORed set of ANDed conditions
(Disjunctive Normal Form, or DNF) or an ANDed set of ORed conditions
(Conjunctive Normal Form, or CNF). Individual conditions may either be
negated (NOT C) or unnegated (C). The Propagated Key Property "System.Name"

System.Name works the same way here as it does for the class
PolicyGroup. See Section 6.2.2 for details. actions specified by a

Moore, et al. Expires: Oct 1999 + 6 months [Page 24] 27]

Internet Draft Policy Core Information Model October 1999

6.3.3. The Key Property "PolicyRuleName"

This property provides a user-friendly name for a policy rule, and is
normally what will be displayed

PolicyRule are to be performed if and only if the end-user as the instance name.
It PolicyRule condition
(whether it is defined as follows:

NAME PolicyRuleName
DESCRIPTION The user-friendly name of this policy rule.
SYNTAX string
QUALIFIER key

6.3.4. represented in DNF or CNF) evaluates to TRUE.

The Property "Enabled"

This property indicates whether conditions and actions associated with a policy rule is currently enabled,
from an ADMINISTRATIVE point are modeled,
respectively, with subclasses of view. Its purpose is to allow a
policy administrator the classes PolicyCondition and
PolicyAction. These condition and action objects are tied to enable or disable
instances of PolicyRule by the ConditionInPolicyRule and
ActionInPolicyRule aggregations.

As illustrated above in Section 3, a policy rule without having
to add it to, may also be
associated with one or remove it from, the more policy repository.

The property also supports the value 'enabledForDebug'. When the
property has this value, time periods, indicating the entity evaluating
schedule according to which the policy conditions rule is active and inactive.
In this case it is being told to evaluate the conditions for PolicyRuleValidityPeriod aggregation that
provides the linkage.

A policy rule, but not
to perform the actions if the conditions evaluate to TRUE. This value
serves as a debug vehicle when attempting to determine what policies
would execute rule is illustrated conceptually in a particular scenario, without taking any actions to
change state during Figure 7. below.

+------------------------------------------------+
| PolicyRule |
| |
| +--------------------+ +-----------------+ |
| | PolicyCondition(s) | | PolicyAction(s) | |
| +--------------------+ +-----------------+ |
| |
| +------------------------------+ |
| | PolicyTimePeriodCondition(s) | |
| +------------------------------+ |
+------------------------------------------------+

Figure 7. Overview of the debugging. PolicyRule Class

The PolicyRule class uses the property definition is as follows:

NAME Enabled
DESCRIPTION An enumeration indicating ConditionListType, to indicate
whether a policy the conditions for the rule is
administratively enabled, administratively
disabled, are in DNF or enabled for debug mode.
SYNTAX uint16
VALUES enabled(1), disabled(2), enabledForDebug(3)
DEFAULT VALUE enabled(1)

6.3.5. CNF. The Property "ConditionListType"

This property is used
ConditionInPolicyRule aggregation contains two additional properties
to specify whether complete the list representation of policy conditions
associated with this policy rule the rule's conditional expression.
The first of these properties is in disjunctive normal form (DNF) an integer to partition the
referenced conditions into one or conjunctive normal form (CNF). If this property is not present, more sets, and the list type defaults second is a
Boolean to DNF. The property definition indicate whether a referenced condition is as follows:

NAME negated. An
example shows how ConditionListType
DESCRIPTION Indicates whether the list and these two additional
properties provide a unique representation of a set of policy conditions
associated with this policy rule is in disjunctive
normal form (DNF)
either DNF or conjunctive normal form (CNF).
SYNTAX uint16
VALUES DNF(1), CNF(2)
DEFAULT VALUE DNF(1) CNF.

Suppose we have a PolicyRule that aggregates five PolicyConditions C1
through C5, with the following values in the properties of the five
ConditionInPolicyRule relationships:

Moore, et al. Expires: Oct 1999 + 6 months [Page 25] 28]

Internet Draft Policy Core Information Model October 1999

6.3.6. The Property "RuleUsage"

This property

If ConditionListType = DNF, then the overall condition for the
PolicyRule is:

(C1 AND (NOT C2) AND C3) OR (C4 AND C5)

On the other hand, if ConditionListType = CNF, then the overall
condition for the PolicyRule is:

(C1 OR (NOT C2) OR C3) AND (C4 OR C5)

In both cases, there is a free-form string an unambiguous specification of the overall
condition that recommends how this policy
should be used. is tested to determine whether to perform the actions
associated with the PolicyRule.

The property class definition is as follows:

NAME PolicyRuleUsage PolicyRule
DESCRIPTION This property is used to provide guidelines on how
this The central class for representing the "If
Condition then Action" semantics associated with a
policy should be used.
SYNTAX string

6.3.7. rule.
DERIVED FROM Policy
ABSTRACT FALSE
PROPERTIES System.CreationClassName[key]
System.Name[key]
CreationClassName[key]
PolicyRuleName[key]
Enabled
ConditionListType
RuleUsage
Priority
Mandatory
SequencedActions

6.3.1. The Propagated Key Property "Priority"

This property provides a non-negative integer "System.CreationClassName"

System.CreationClassName works the same way here as it does for prioritizing policy
rules relative to each other. For policy rules that have this
property, larger integer values indicate higher priority. Since one
purpose of this property is to allow specific, ad hoc policy rules to
temporarily override established policy rules, an instance that has
this property set has a higher priority than all instances that lack
it.

Prioritization among policy rules provides a simple and efficient
mechanism for resolving policy conflicts.

The property definition is as follows:

NAME Priority
DESCRIPTION A non-negative integer for prioritizing this
PolicyRule relative to other PolicyRules. A larger
value indicates a higher priority.
SYNTAX uint16
DEFAULT VALUE 0

6.3.8. The Property "Mandatory"

This property indicates whether evaluation (and possibly action
execution) of a PolicyRule is mandatory or not. Its concept is
similar to the ability to mark packets
class PolicyGroup. See Section 6.2.1 for delivery or possible
discard, based on network traffic and device load. details.

6.3.2. The evaluation of a PolicyRule MUST be attempted if the Mandatory
property value is TRUE. If the Mandatory property value of a
PolicyRule is FALSE, then the evaluation of Propagated Key Property "System.Name"

System.Name works the rule is "best effort"
and MAY be ignored.

The property definition is same way here as follows:

NAME Mandatory
DESCRIPTION A flag indicating that the evaluation of the
PolicyConditions and execution of PolicyActions (if it does for the condition list evaluates to TRUE) is required.
SYNTAX boolean
DEFAULT VALUE TRUE class
PolicyGroup. See Section 6.2.2 for details.

Moore, et al. Expires: Oct 1999 + 6 months [Page 26] 29]

Internet Draft Policy Core Information Model October 1999

6.3.9.

6.3.3. The Key Property "SequencedActions" "CreationClassName"

This property gives a policy administrator a way of specifying how identifies the
ordering of class or subclass used in the policy actions associated with creation of
this PolicyRule is to
be interpreted. Three values are supported:

o mandatory(1): Do the actions in instance.

NAME CreationClassName
DESCRIPTION The name of the indicated order, class or don't do
them at all.

o recommended(2): Do the actions subclass used in the indicated order if you can,
but if you can't do them in
creation of this order, do them in another order if
you can.

o dontCare(3): Do them -- I don't care about the order.

When error / event reporting is addressed for the Policy Framework,
suitable codes will be defined instance.
SYNTAX string[MaxLen 256]
QUALIFIER key

6.3.4. The Key Property "PolicyRuleName"

This property provides a user-friendly name for reporting that a set of actions
could not policy rule, and is
normally what will be performed in an order specified displayed to the end-user as mandatory (and thus
were not performed at all), that a set of actions could not be
performed in a recommended order (and moreover could not be performed
in any order), or that a set of actions could not be performed in a
recommended order (but were performed in a different order). The
property definition the instance name.
It is defined as follows:

NAME SequencedActions PolicyRuleName
DESCRIPTION An enumeration indicating how to interpret the
action ordering indicated via the
ActionInPolicyRule aggregation.
SYNTAX uint16
VALUES mandatory(1), recommended(2), dontCare(3)
DEFAULT VALUE dontCare(3)

6.4. The Class "PolicyCondition" The purpose user-friendly name of this policy rule.
SYNTAX string
QUALIFIER key

6.3.5. The Property "Enabled"

This property indicates whether a policy condition rule is currently enabled,
from an ADMINISTRATIVE point of view. Its purpose is to determine whether allow a
policy administrator to enable or not disable a policy rule without having
to add it to, or remove it from, the
set of actions (aggregated in policy repository.

The property also supports the PolicyRule that value 'enabledForDebug'. When the condition
applies to) should be executed or not. For
property has this value, the purposes of entity evaluating the Policy
Core Information Model, all that matters about an individual
PolicyCondition policy conditions
is that it evaluates to TRUE or FALSE. (The
individual PolicyConditions associated with a PolicyRule are combined being told to form a compound expression in either DNF or CNF, but this is
accomplished via the ConditionListType property, discussed above, and
by evaluate the properties of conditions for the ConditionInPolicyRule aggregation, introduced
above and discussed further in Section 7.6 below.) A logical
structure WITHIN an individual PolicyCondition may also be introduced, policy rule, but this would have not
to be done perform the actions if the conditions evaluate to TRUE. This value
serves as a debug vehicle when attempting to determine what policies
would execute in a subclass of PolicyCondition. particular scenario, without taking any actions to
change state during the debugging.

The property definition is as follows:

NAME Enabled
DESCRIPTION An enumeration indicating whether a policy rule is
administratively enabled, administratively
disabled, or enabled for debug mode.
SYNTAX uint16
VALUES enabled(1), disabled(2), enabledForDebug(3)
DEFAULT VALUE enabled(1)

Moore, et al. Expires: Oct 1999 + 6 months [Page 27] 30]

Internet Draft Policy Core Information Model October 1999

+---------------------------------------------------------------+
| Policy Conditions in DNF |
| +-------------------------+ +-----------------------+ |
| | AND list | | AND

6.3.6. The Property "ConditionListType"

This property is used to specify whether the list | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | ... | | PolicyCondition | | |
| | +-------------------+ | ORed | +-----------------+ | |
| | ... | | ... | |
| | ANDed | | ANDed | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| +-------------------------+ +-----------------------+ |
+---------------------------------------------------------------+

Figure 7. Overview of Policy Conditions in DNF

This figure illustrates that when policy conditions are
associated with this policy rule is in DNF, there
are one disjunctive normal form (DNF)
or more sets of conditions that are ANDed together to conjunctive normal form AND
lists. An AND (CNF). If this property is not present,
the list evaluates type defaults to TRUE if and only if all DNF. The property definition is as follows:

NAME ConditionListType
DESCRIPTION Indicates whether the list of its
constituent policy conditions evaluate
associated with this policy rule is in disjunctive
normal form (DNF) or conjunctive normal form (CNF).
SYNTAX uint16
VALUES DNF(1), CNF(2)
DEFAULT VALUE DNF(1)

6.3.7. The Property "RuleUsage"

This property is a free-form string that recommends how this policy
should be used. The property definition is as follows:

NAME PolicyRuleUsage
DESCRIPTION This property is used to TRUE. provide guidelines on how
this policy should be used.
SYNTAX string

6.3.8. The overall condition then
evaluates Property "Priority"

This property provides a non-negative integer for prioritizing policy
rules relative to TRUE if and only if at least each other. For policy rules that have this
property, larger integer values indicate higher priority. Since one
purpose of its constituent AND
lists evaluates this property is to TRUE.

+---------------------------------------------------------------+
| allow specific, ad hoc policy rules to
temporarily override established policy rules, an instance that has
this property set has a higher priority than all instances that lack
it.

Prioritization among policy rules provides a simple and efficient
mechanism for resolving policy conflicts.

The property definition is as follows:

NAME Priority
DESCRIPTION A non-negative integer for prioritizing this
PolicyRule relative to other PolicyRules. A larger
value indicates a higher priority.
SYNTAX uint16
DEFAULT VALUE 0

6.3.9. The Property "Mandatory"

This property indicates whether evaluation (and possibly action
execution) of a PolicyRule is mandatory or not. Its concept is

Moore, et al. Expires: Oct 1999 + 6 months [Page 31]

similar to the ability to mark packets for delivery or possible
discard, based on network traffic and device load.

The evaluation of a PolicyRule MUST be attempted if the Mandatory
property value is TRUE. If the Mandatory property value of a
PolicyRule is FALSE, then the evaluation of the rule is "best effort"
and MAY be ignored.

The property definition is as follows:

NAME Mandatory
DESCRIPTION A flag indicating that the evaluation of the
PolicyConditions and execution of PolicyActions (if
the condition list evaluates to TRUE) is required.
SYNTAX boolean
DEFAULT VALUE TRUE

6.3.10. The Property "SequencedActions"

This property gives a policy administrator a way of specifying how the
ordering of the policy actions associated with this PolicyRule is to
be interpreted. Three values are supported:

o mandatory(1): Do the actions in the indicated order, or don't do
them at all.

o recommended(2): Do the actions in the indicated order if you can,
but if you can't do them in this order, do them in another order if
you can.

o dontCare(3): Do them -- I don't care about the order.

When error / event reporting is addressed for the Policy Framework,
suitable codes will be defined for reporting that a set of actions
could not be performed in an order specified as mandatory (and thus
were not performed at all), that a set of actions could not be
performed in a recommended order (and moreover could not be performed
in any order), or that a set of actions could not be performed in a
recommended order (but were performed in a different order). The
property definition is as follows:

NAME SequencedActions
DESCRIPTION An enumeration indicating how to interpret the
action ordering indicated via the
ActionInPolicyRule aggregation.
SYNTAX uint16
VALUES mandatory(1), recommended(2), dontCare(3)
DEFAULT VALUE dontCare(3)

Moore, et al. Expires: Oct 1999 + 6 months [Page 32]

Internet Draft Policy Core Information Model October 1999

6.4. The Class "PolicyCondition"

The purpose of a policy condition is to determine whether or not the
set of actions (aggregated in the PolicyRule that the condition
applies to) should be executed or not. For the purposes of the Policy
Core Information Model, all that matters about an individual
PolicyCondition is that it evaluates to TRUE or FALSE. (The
individual PolicyConditions associated with a PolicyRule are combined
to form a compound expression in either DNF or CNF, but this is
accomplished via the ConditionListType property, discussed above, and
by the properties of the ConditionInPolicyRule aggregation, introduced
above and discussed further in Section 7.6 below.) A logical
structure WITHIN an individual PolicyCondition may also be introduced,
but this would have to be done in a subclass of PolicyCondition.

+---------------------------------------------------------------+
| Policy Conditions in DNF |
| +-------------------------+ +-----------------------+ |
| | AND list | | AND list | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | ... | | PolicyCondition | | |
| | +-------------------+ | ORed | +-----------------+ | |
| | ... | | ... | |
| | ANDed | | ANDed | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| +-------------------------+ +-----------------------+ |
+---------------------------------------------------------------+

Figure 8. Overview of Policy Conditions in DNF

This figure illustrates that when policy conditions are in DNF, there
are one or more sets of conditions that are ANDed together to form AND
lists. An AND list evaluates to TRUE if and only if all of its
constituent conditions evaluate to TRUE. The overall condition then
evaluates to TRUE if and only if at least one of its constituent AND
lists evaluates to TRUE.

Moore, et al. Expires: Oct 1999 + 6 months [Page 33]

Internet Draft Policy Core Information Model October 1999

+---------------------------------------------------------------+
| Policy Conditions in CNF |
| +-------------------------+ +-----------------------+ |
| | OR list | | OR list | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | ... | | PolicyCondition | | |
| | +-------------------+ | ANDed | +-----------------+ | |
| | ... | | ... | |
| | ORed | | ORed | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | | +-------------------+ | | +-----------------+ | |
| | |
| +-------------------------+ +-----------------------+ |
+---------------------------------------------------------------+

Figure 9. Overview of Policy Conditions in CNF

In this figure, the policy conditions are in CNF. Consequently, there
are one or more OR lists, each of which evaluates to TRUE if and only
if at least one of its constituent conditions evaluates to TRUE. The
overall condition then evaluates to TRUE if and only if ALL of its
constituent OR lists evaluate to TRUE.

The class definition of PolicyCondition is as follows:

NAME PolicyCondition
DESCRIPTION A class representing a rule-specific or reusable
policy condition to be evaluated in conjunction
with a policy rule.
DERIVED FROM Policy
ABSTRACT FALSE
PROPERTIES SystemCreationClassName[key]
SystemName[key]
PolicyRuleCreationClassName[key]
PolicyRuleName[key]
CreationClassName[key]
PolicyConditionName[key]

6.4.1. The Key Property "SystemCreationClassName"

This property helps to identify the System object in whose scope this
instance of PolicyCondition exists. For a rule-specific policy
condition, this is the system in whose context the policy rule is
defined. For a reusable policy condition, this is the instance of
PolicyRepository (which is a subclass of System) that holds the policy
condition.

Moore, et al. Expires: Oct 1999 + 6 months [Page 34]

Internet Draft Policy Core Information Model October 1999

Note that this property, and the analogous property SystemName, do not
represent propagated keys from an instance of the class System. (If
they did, they would be written with a dot: System.CreationClassName,
System.Name.) Instead, they are properties defined in the context of
this class, which repeat the values from the instance of System to
which the instance containing them is related, either directly via the
ConditionInPolicyRepository aggregation or indirectly via the
ConditionInPolicyRule aggregation. See Section 5.3.3 for more on this
topic.

This property is defined as follows:

NAME SystemCreationClassName
DESCRIPTION The name of the class or the subclass used in the
creation of the System object in whose scope this
policy condition is defined.
SYNTAX string
QUALIFIER key

6.4.2. The Key Property "SystemName"

This property completes the identification of the System object in
whose scope this instance of PolicyCondition exists. For a rule-
specific policy condition, this is the system in whose context the
policy rule is defined. For a reusable policy condition, this is the
instance of PolicyRepository (which is a subclass of System) that
holds the policy condition.

This property is defined as follows:

NAME SystemName
DESCRIPTION The name of the System object in whose scope this
policy condition is defined.
SYNTAX string
QUALIFIER key

6.4.3. The Key Property "PolicyRuleCreationClassName"

For a rule-specific policy condition, this property helps to identify
the policy rule in whose scope this instance of PolicyCondition | | | |
exists. For a reusable policy condition, this property returns a
special value, "No Rule", indicating that this instance of
PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| | +-------------------+ | | +-----------------+ | |
| | | is not unique to one policy rule.

This property is defined as follows:

NAME PolicyRuleCreationClassName
DESCRIPTION For a rule-specific policy condition, this property
identifies the class of the policy rule instance in
whose scope this instance of PolicyCondition | | ... | |
exists. For a reusable policy condition, this
property returns a special value, "No Rule",

Moore, et al. Expires: Oct 1999 + 6 months [Page 35]

Internet Draft Policy Core Information Model October 1999

SYNTAX string[MaxLen 256]
QUALIFIER key

6.4.4. The Key Property "PolicyRuleName"

For a rule-specific policy condition, this property completes the
identification of the policy rule in whose scope this instance of
PolicyCondition exists. For a reusable policy condition, this
property returns a special value, "No Rule", indicating that this
instance of PolicyCondition is not unique to one policy rule.

This property is defined as follows:

NAME PolicyRuleName
DESCRIPTION For a rule-specific policy condition, the name of
the PolicyRule object with which this condition is
associated. For a reusable policy condition, a
special value, "No Rule", indicating that this
condition is reusable.
SYNTAX string
QUALIFIER key

6.4.5. The Key Property "CreationClassName"

This property identifies the class or subclass used in the creation of
this instance.

NAME CreationClassName
DESCRIPTION The name of the class or subclass used in the
creation of this instance.
SYNTAX string[MaxLen 256]
QUALIFIER key

6.4.6. The Key Property "PolicyConditionName"

This property provides a user-friendly name for a policy condition,
and is normally what will be displayed to the end-user as the instance
name. It is defined as follows:

NAME PolicyConditionName
DESCRIPTION The user-friendly name of this policy condition.
SYNTAX string
QUALIFIER key

Moore, et al. Expires: Oct 1999 + 6 months [Page 36]

Internet Draft Policy Core Information Model October 1999

6.5. The Class "PolicyTimePeriodCondition"

This class provides a means of representing the time periods during
which a policy rule is valid, i.e., active. At all times that fall
outside these time periods, the policy rule has no effect. A policy
rule is treated as valid at all times if it does not specify a
PolicyTimePeriodCondition.

In some cases a Policy Consumer may need to perform certain setup /
cleanup actions when a policy rule becomes active / inactive. For
example, sessions that were established while a policy rule was active
might need to be taken down when the rule becomes inactive. In other
cases, however, such sessions might be left up: in this case, the
effect of deactivating the policy rule would just be to prevent the
establishment of new sessions. Any such setup / cleanup behaviors on
validity period transitions must be specified in a subclass of
PolicyRule. If such behaviors need to be under the control of the
policy administrator, then a mechanism to allow this control must also
be specified in the subclass.

PolicyTimePeriodCondition is defined as a subclass of PolicyCondition.
This is to allow the inclusion of time-based criteria in the AND/OR
condition definitions for a PolicyRule.

Instances of this class may have up to five properties identifying
time periods at different levels. The values of all the properties
present in an instance are ANDed | +-----------------+ | |
| | ... | | ... | |
| | ORed | | ORed | |
| | +-------------------+ | | +-----------------+ | |
| | | PolicyCondition | | | | together to determine the validity
period(s) for the instance. For example, an instance with an overall
validity range of January 1, 1999 through December 31, 1999; a month
mask of "001100000000" (March and April); a day-of-the-week mask of
"0000010" (Fridays); and a time of day range of 0800 through 1600
would represent the following time periods:

Friday, March 5, 1999, from 0800 through 1600;
Friday, March 12, 1999, from 0800 through 1600;
Friday, March 19, 1999, from 0800 through 1600;
Friday, March 26, 1999, from 0800 through 1600;
Friday, April 2, 1999, from 0800 through 1600;
Friday, April 9, 1999, from 0800 through 1600;
Friday, April 16, 1999, from 0800 through 1600;
Friday, April 23, 1999, from 0800 through 1600;
Friday, April 30, 1999, from 0800 through 1600.

Properties not present in an instance of PolicyTimePeriodCondition are
implicitly treated as having their value "always enabled". Thus, in
the example above, the day-of-the-month mask is not present, and so
the validity period for the instance implicitly includes a day-of-the-
month mask containing 31 1's. If we apply this "missing property"
rule to its fullest, we see that there is a second way to indicate
that a policy rule is always enabled: have it point to an instance of

Moore, et al. Expires: Oct 1999 + 6 months [Page 37]

Internet Draft Policy Core Information Model October 1999

PolicyTimePeriodCondition whose only properties are its naming
properties.

The class definition is as follows. Note that instances of this class
are named with the inherited key properties SystemCreationClassName,
SystemName, PolicyRuleName, and PolicyConditionName.

NAME PolicyTimePeriodCondition
DESCRIPTION A class that provides the capability of enabling /
disabling a policy rule according to a pre-
determined schedule.
DERIVED FROM PolicyCondition | | |
| | +-------------------+ | | +-----------------+ | |
| +-------------------------+ +-----------------------+ |
+---------------------------------------------------------------+

Figure 8. Overview
ABSTRACT FALSE
PROPERTIES TimePeriod
MonthOfYearMask
DayOfMonthMask
DayOfWeekMask
TimeOfDayMask
ApplicableTimeZone

6.5.1. The Property "TimePeriod"

This property identifies an overall range of calendar dates and times
over which a policy rule is valid. It is formatted as a string
consisting of a start date and time, then a colon (':'), and followed
by an end date and time. The first date indicates the beginning of Policy Conditions in CNF

In
the range, while the second date indicates the end. Thus, the second
date and time must be later than the first. Dates are expressed as
substrings of the form "yyyymmddhhmmss". For example:

19990101080000:19990131120000

January 1, 1999, 0800 through January 31, 1999, noon

There are three special cases that can also be represented with this figure,
format:

o If the date before the ':' is omitted, then the property indicates
that a policy conditions are in CNF. Consequently, there rule is valid [from now] until the date that appears
after the ':'.

o If the date after the ':' is omitted, then the property indicates
that a policy rule becomes valid on the date that appears before
the ':', and remains valid from that point on.

o If both dates are one or more OR lists, each of which evaluates to TRUE omitted (i.e., if and the string contains only
if at least one of its constituent conditions evaluates to TRUE. the
':' character), then the property indicates that a policy rule is
valid now, and remains valid from now on.

The property definition is as follows:

NAME TimePeriod

Moore, et al. Expires: Oct 1999 + 6 months [Page 28] 38]

Internet Draft Policy Core Information Model October 1999

overall condition then evaluates to TRUE if and only if ALL of its
constituent OR lists evaluate to TRUE.

DESCRIPTION The class definition range of PolicyCondition is as follows:

NAME PolicyCondition
DESCRIPTION A class representing a rule-specific or reusable
policy condition to be evaluated in conjunction
with calendar dates on which a policy rule.
DERIVED FROM Policy
ABSTRACT FALSE
PROPERTIES SystemCreationClassName[key]
SystemName[key]
PolicyRuleName[key]
PolicyConditionName[key]

6.4.1. rule
is valid.
SYNTAX string
FORMAT [yyyymmddhhmmss]:[yyyymmddhhmmss]

6.5.2. The Key Property "SystemCreationClassName"

This "MonthOfYearMask"

The purpose of this property helps is to identify refine the System object in whose scope this
instance definition of PolicyCondition exists. For a rule-specific policy
condition, this the valid
time period that is defined by the system in whose context TimePeriod property, by explicitly
specifying which months the policy rule is
defined. For a reusable valid for. These properties
work together, with the TimePeriod used to specify the overall time
period that the policy condition, this is valid for, and the instance of
PolicyRepository (which is a subclass MonthOfYearMask used to
pick out which months of System) that holds time period the policy
condition.

Note that this property, is valid for.

This property is formatted as a string containing 12 ASCII '0's and
'1's, where the analogous property SystemName, do not
represent propagated keys from an instance of '1's identify the class System. (If
they did, they would be written months (beginning with January) in
which the policy rule is valid. The value "000010010000", for
example, indicates that a dot: System.CreationClassName,
System.Name.) Instead, they are properties defined policy rule is valid only in the context of months May
and August.

If this class, which repeat property is omitted, then the values from policy rule is treated as valid
for all twelve months. The property definition is as follows:

NAME MonthOfYearMask
DESCRIPTION A mask identifying the instance months of System to
which the instance containing them year in which
a policy rule is related, either directly via the
ConditionInPolicyRepository aggregation or indirectly via the
ConditionInPolicyRule aggregation. See Section 5.2.2 for more on valid.
SYNTAX string
FORMAT A string of 12 ASCII '0's and '1's.

6.5.3. The Property "DayOfMonthMask"

The purpose of this
topic.

This property is to refine the definition of the valid
time period that is defined as follows:

NAME SystemCreationClassName
DESCRIPTION The name by the TimePeriod property, by explicitly
specifying which days of the class or month the subclass policy is valid for. These
properties work together, with the TimePeriod used in to specify the
creation
overall time period that the policy is valid for, and the
DayOfMonthMask used to pick out which days of the System object month in whose scope this that time
period the policy condition is defined.
SYNTAX string
QUALIFIER key

6.4.2. The Key Property "SystemName" valid for.

This property completes is formatted as a string containing 62 ASCII '0's and
'1's, where the identification of '1's identify the System object in
whose scope this instance days of PolicyCondition exists. For a rule-
specific the month on which the
policy condition, this rule is valid. The encoding is analogous to that used for the system
schedDay object in whose context the
policy rule DISMAN-SCHEDULE-MIB (currently a Proposed
Standard, published as RFC 2591). The difference is that the MIB
object is defined. For a reusable policy condition, bit string (defined with the SMIv2 BITS construct), while
this property is a string of ASCII '0's and '1's.

To illustrate how the
instance days of PolicyRepository (which is a subclass of System) that
holds month are represented, we can quote
the policy condition. definition from the DISMAN-SCHEDULE-MIB:

Moore, et al. Expires: Oct 1999 + 6 months [Page 29] 39]

Internet Draft Policy Core Information Model October 1999

This property is defined as follows:

NAME SystemName

schedDay OBJECT-TYPE
SYNTAX BITS {
d1(0), d2(1), d3(2), d4(3), d5(4),
d6(5), d7(6), d8(7), d9(8), d10(9),
d11(10), d12(11), d13(12), d14(13), d15(14),
d16(15), d17(16), d18(17), d19(18), d20(19),
d21(20), d22(21), d23(22), d24(23), d25(24),
d26(25), d27(26), d28(27), d29(28), d30(29),
d31(30),
r1(31), r2(32), r3(33), r4(34), r5(35),
r6(36), r7(37), r8(38), r9(39), r10(40),
r11(41), r12(42), r13(43), r14(44), r15(45),
r16(46), r17(47), r18(48), r19(49), r20(50),
r21(51), r22(52), r23(53), r24(54), r25(55),
r26(56), r27(57), r28(58), r29(59), r30(60),
r31(61)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION The name
"The set of the System object days in whose scope this
policy condition is defined.
SYNTAX string
QUALIFIER key

6.4.3. The Key Property "PolicyRuleName"

For a rule-specific policy condition, this property identifies the
policy rule in whose scope this instance month on which a scheduled action
should take place. There are two sets of PolicyCondition exists.
For bits one can
use to define the day within a reusable policy condition, this property returns month:

Enumerations starting with the letter 'd' indicate a special
value,
day in a month relative to the zero-length string (""), indicating that this instance first day of
PolicyCondition is not unique to one policy rule.

This property is defined as follows:

NAME PolicyRuleName
DESCRIPTION For a rule-specific policy condition, the name month.
The first day of the PolicyRule object with which this condition is
associated. For a reusable policy condition, month can therefore be specified
by setting the bit d1(0) and d31(30) means the last
day of a
special value, month with 31 days.

Enumerations starting with the zero-length string (""),
indicating that this condition is reusable.
SYNTAX string
QUALIFIER key

6.4.4. The Key Property "PolicyConditionName"

This property provides letter 'r' indicate a user-friendly name for
day in a policy condition,
and is normally what will be displayed month in reverse order, relative to the end-user as the instance
name. It is defined as follows:

NAME PolicyConditionName
DESCRIPTION The user-friendly name last
day of this policy condition.
SYNTAX string
QUALIFIER key

6.5. The Class "PolicyTimePeriodCondition"

This class provides a month. The last day in the month can therefore
be specified by setting the bit r1(31) and r31(61) means of representing
the time periods during
which first day of a policy rule is valid, i.e., active. At all times that fall
outside these time periods, month with 31 days.

Setting multiple bits will include several days in the policy rule has no effect. A policy
rule is treated as valid at set
of possible days for this schedule. Setting all times if it does not specify a
PolicyTimePeriodCondition.

In some cases a Policy Consumer may need bits will
cause the scheduler to ignore the day within a month.
Setting all bits starting with the letter 'd' or the
letter 'r' will also cause the scheduler to perform certain setup /
cleanup actions when ignore the
day within a policy rule becomes active / inactive. For month."
DEFVAL { {} }
::= { schedEntry 7 }

Applying this to the DayOfMonthMask property, we see that the value
"11100000000000000000000000000001110000000000000000000000000000", for
example, sessions indicates that were established while a policy rule was active
might need to be taken down when is valid only on the rule becomes inactive. In other
cases, however, such sessions might be left up: in this case, first three
days of each month and the
effect last three days of deactivating each month. For months
with fewer than 31 days, the policy rule would just be digits corresponding to prevent days that the

Moore, et al. Expires: Oct 1999 + 6 months [Page 30] 40]

Internet Draft Policy Core Information Model October 1999

establishment of new sessions. Any such setup / cleanup behaviors on
validity period transitions must be specified in a subclass of
PolicyRule. If such behaviors need to be under the control of the
policy administrator, then a mechanism to allow this control must also
be specified

months do not have (counting in the subclass.

PolicyTimePeriodCondition both directions) are ignored. The
property definition is defined as a subclass of PolicyCondition.
This is to allow the inclusion of time-based criteria in the AND/OR
condition definitions for a PolicyRule.

Instances of this class may have up to five properties follows:

NAME DayOfMonthMask
DESCRIPTION A mask identifying
time periods at different levels. The values of all the properties
present in an instance are ANDed together to determine the validity
period(s) for the instance. For example, an instance with an overall
validity range days of January 1, 1999 through December 31, 1999; a the month
mask of "001100000000" (March and April); on which a day-of-the-week mask
policy rule is valid.
SYNTAX string
FORMAT A string of
"0000100" (Fridays); 62 ASCII '0's and a time '1's.

6.5.4. The Property "DayOfWeekMask"

The purpose of day range this property is to refine the definition of 0800 through 1600
would represent the following valid
time periods:

Attributes not present in an instance period that is defined by the TimePeriod property by explicitly
specifying which days of PolicyTimePeriodCondition are
implicitly treated as having their value "always enabled". Thus, in the example above, week the day-of-the-month mask policy is not present, valid for. These
properties work together, with the TimePeriod used to specify the
overall time period that the policy is valid for, and so the validity
DayOfWeekMask used to pick out which days of the week in that time
period for the instance implicitly includes policy is valid for.

This property is formatted as a day-of-the-
month mask string containing 31 1's. If we apply this "missing property" 7 ASCII '0's and
'1's, where the '1's identify the days of the week (beginning with
Sunday and going up through Saturday) on which the policy rule to its fullest, we see that there is a second way to indicate
valid. The value "0111110", for example, indicates that a policy rule
is always enabled: have it point to an instance of
PolicyTimePeriodCondition whose only properties are its naming
properties. valid Monday through Friday.

The class property definition is as follows. Note that instances of this class
are named with the inherited key properties CreationClassName and
PolicyRuleName. follows:

NAME PolicyTimePeriodCondition DayOfWeekMask
DESCRIPTION A class that provides mask identifying the capability days of enabling /
disabling the week on which a
policy rule according to a pre-
determined schedule.
DERIVED FROM PolicyCondition
ABSTRACT FALSE
PROPERTIES TimePeriod
MonthOfYearMask

Moore, et al. Expires: Oct 1999 + 6 months [Page 31]

Internet Draft Policy Core Information Model October 1999

DayOfMonthMask
DayOfWeekMask
TimeOfDayMask
ApplicableTimeZone

6.5.1. is valid.
SYNTAX string
FORMAT A string of 7 ASCII '0's and '1's.

6.5.5. The Property "TimePeriod"

This "TimeOfDayMask"

The purpose of this property identifies an overall is to refine the definition of the valid
time period that is defined by the TimePeriod property by explicitly
specifying a range of calendar dates and times
over in a day the policy is valid for. These
properties work together, with the TimePeriod used to specify the
overall time period that the policy is valid for, and the
TimeOfDayMask used to pick out which range of time periods in a given
day of that time period the policy rule is valid. It valid for.

This property is formatted as a string
consisting of a start date and time, then containing two times, separated
by a colon (':'), and followed
by an end date and time. (':'). The first date time indicates the beginning of the
range, while the second date time indicates the end. Thus, Times are expressed
as substrings of the form "hhmmss".

The second
date and time must be substring always identifies a later time than the first. Dates are expressed as
substrings first
substring. To allow for ranges that span midnight, however, the value
of the form "yyyymmddhhmmss". For example:

19990101080000:19990131120000

January 1, 1999, 0800 through January 31, 1999, noon

There are three special cases that can also second string may be represented with this
format:

o If smaller than the date before value of the ':' is omitted, then first
substring. Thus, "080000:210000" identifies the property indicates
that a policy rule is valid [from now] range from 0800 until

Moore, et al. Expires: Oct 1999 + 6 months [Page 41]

Internet Draft Policy Core Information Model October 1999

2100, while "210000:080000" identifies the date that appears
after range from 2100 until 0800
of the ':'.

o If following day.

When a range spans midnight, it by definition includes parts of two
successive days. When one of these days is also selected by either
the date after MonthOfYearMask, DayOfMonthMask, and/or DayOfWeekMask, but the ':'
other day is omitted, not, then the property indicates
that a policy rule becomes valid on is active only during the date that appears before portion of
the ':', and remains valid from range that point on.

o If both dates are omitted (i.e., falls on the selected day. For example, if the string contains only range
extends from 2100 until 0800, and the
':' character), day of week mask selects Monday
and Tuesday, then the property indicates that a policy rule is
valid now, and remains valid from now on. active during the following three
intervals:

From midnight Sunday until 0800 Monday;
From 2100 Monday until 0800 Tuesday;
From 2100 Tuesday until 21:59:59 Tuesday.

The property definition is as follows:

NAME TimePeriod TimeOfDayMask
DESCRIPTION The range of calendar dates on times at which a policy rule is valid.
If the second time is earlier than the first, then
the interval spans midnight.
SYNTAX string
FORMAT [yyyymmddhhmmss]:[yyyymmddhhmmss]

6.5.2. hhmmss:hhmmss

6.5.6. The Property "MonthOfYearMask"

The purpose of this "ApplicableTimeZone"

This property is used to refine the definition of the valid explicitly define a time period that is defined zone for use by the
TimePeriod property, by explicitly
specifying which months and the policy various Mask properties. If this property is valid for. These properties
work together, with the TimePeriod used to specify the overall not
present, then local time
period that the policy is valid for, and (at the MonthOfYearMask used to
pick out which months of that time period location where the policy PolicyRule is valid for.

Moore, et al. Expires: Oct 1999 + 6 months [Page 32]

Internet Draft Policy Core Information Model October 1999
enforced) is assumed.

This property specifies time in UTC, using an offset indicator. The
UTC offset indicator is formatted as either a string containing 12 ASCII '0's and
'1's, where the '1's identify the months (beginning with January) in
which 'Z', indicating UTC, or a substring
of the policy rule is valid. The value "000010010000", for following form:

'+' or '-' direction from UTC: '+' = east, '-' = west

hh hours from UTC (00..13)

mm minutes from UTC (00..59)

For example, the string "+0200" indicates that a policy rule is valid only in the months May time zone two hours east
of UTC, and August.

If this property is omitted, then the policy rule is treated as valid
for all twelve months. string "-0830" indicates a time zone 8.5 hours west of
UTC.

The property definition is as follows:

NAME MonthOfYearMask ApplicableTimeZone
DESCRIPTION A mask identifying the months of The time zone for the year in which
a policy rule is valid. PolicyTimePeriodCondition.
SYNTAX string

Moore, et al. Expires: Oct 1999 + 6 months [Page 42]

Internet Draft Policy Core Information Model October 1999

FORMAT A string of 12 ASCII '0's and '1's.

6.5.3. either 'Z' (UTC) or <'+'|'-'><hhmm>

6.6. The Property "DayOfMonthMask" Class "VendorPolicyCondition"

The purpose of this property class is to refine the definition of the valid
time period that is defined by the TimePeriod property, by explicitly
specifying which days of the month the provide a general escape mechanism for
representing policy is valid for. These
properties work together, conditions that have not been modeled with
specific properties. Instead, the TimePeriod two properties Constraint and
ConstraintEncoding are used to specify the
overall time period that define the policy is valid for, content and the
DayOfMonthMask used to pick out which days format of the month in that time
period the policy
condition, as explained below.

As its name suggests, this class is valid for.

This property intended for vendor-specific
extensions to the Policy Core Information Model. Standardized
extensions are not expected to use this class.

The class definition is formatted as follows:

NAME VendorPolicyCondition
DESCRIPTION A class that defines a registered means to describe
a string containing 31 ASCII '0's and
'1's, where the '1's identify the days of the month (beginning with
day 1 and going up through day 31) on which the policy rule is valid. condition.
DERIVED FROM PolicyCondition
ABSTRACT FALSE
PROPERTIES Constraint[ ]
ConstraintEncoding

6.6.1. The value "1110000000000000000000000000000", for example, indicates
that Multi-valued Property "Constraint"

This property provides a general escape mechanism for representing
policy rule is valid only on the first three days of each
month. For months conditions that have not been modeled with fewer than 31 days, specific properties.
The format of the octet strings in the digits corresponding
to days that array is left unspecified in
this definition. It is determined by the OID value stored in the months do not have are ignored. The
property
definition ConstraintEncoding. Since ConstraintEncoding is as follows:

NAME DayOfMonthMask
DESCRIPTION A mask identifying single-
valued, all the days values of Constraint share the month on which a
policy rule same format and
semantics.

NOTE: In version 2.2 of the CIM model [7], there is valid.
SYNTAX string
FORMAT A string no direct way to
represent an array of 31 ASCII '0's and '1's.

6.5.4. The Property "DayOfWeekMask"

The purpose octet strings. (A single octet string can be
represented as an ordered array of uint8's, but this property does not work for
multi-valued properties where each value is an octet string.) CIM
has, however, a mechanism that is essentially equivalent to refine SMI's
(SNMP's) Textual Convention, for refining the definition syntax and/or semantics
of existing data types. Using this mechanism, a representation of
octet strings as character strings (specifically, strings consisting
of an even number of the valid
time period that characters A-F and 0-9) has been defined. In
a future version of CIM, though, it is defined by likely that an actual
octetString data type will be added.

A policy decision point can readily determine whether it supports the TimePeriod property by explicitly
specifying which days
values stored in an instance of Constraint by checking the week the policy is valid for. These
properties work together, with the TimePeriod used to specify OID value
from ConstraintEncoding against the
overall time period that set of OIDs it recognizes. The
action for the policy is valid for, and the
DayOfWeekMask used decision point to pick out which days of the week in that time
period take in case it does not
recognize the policy is valid for.

This property is formatted format of this data could itself be modeled as a string containing 7 ASCII '0's and
'1's, where the '1's identify policy
rule, governing the days behavior of the week (beginning with policy decision point.

Moore, et al. Expires: Oct 1999 + 6 months [Page 33] 43]

Internet Draft Policy Core Information Model October 1999

Monday and going up through Sunday) on which the policy rule is valid.
The value "1111100", for example, indicates that a policy rule is
valid Monday through Friday.

The property definition is defined as follows:

NAME DayOfWeekMask Constraint
DESCRIPTION A mask identifying the days of the week on which a
policy rule is valid.
SYNTAX string
FORMAT A string of 7 ASCII '0's and '1's.

6.5.5. The Property "TimeOfDayMask"

The purpose of this property is to refine the definition of the valid
time period that is defined by the TimePeriod property by explicitly
specifying a range of times in a day the policy is valid for. These
properties work together, with the TimePeriod used to specify the
overall time period that the policy is valid for, and the
TimeOfDayMask used to pick out which range of time periods in a given
day of that time period the policy is valid for.

This property is formatted as a string containing two times, separated
by a colon (':'). The first time indicates the beginning of the
range, while the second time indicates the end. Times are expressed
as substrings of the form "hhmmss".

The second substring always identifies a later time than the first
substring. To allow Escape mechanism for ranges representing constraints that span midnight, however, the value
have not been modeled as specific properties. The
format of the second string may be smaller than the value of values is identified by the first
substring. Thus, "080000:210000" identifies OID
stored in the range from 0800 until
2100, while "210000:080000" property ConstraintEncoding.
SYNTAX octetString

6.6.2. The Property "ConstraintEncoding"

This property identifies the range from 2100 until 0800 encoding and semantics of the following day.

When a range spans midnight, it by definition includes parts of two
successive days. When one Constraint
property values in this instance. The value of these days this property is also selected by either
the MonthOfYearMask, DayOfMonthMask, and/or DayOfWeekMask, but the
other day a
single string, representing a single OID.

The property is not, then defined as follows:

NAME ConstraintEncoding
DESCRIPTION An OID encoded as a string, identifying the format
and semantics for this instance's Constraint
property.
SYNTAX string
QUALIFIER OID

6.7. The Class "PolicyAction"

The purpose of a policy action is active only during to execute one or more operations
that will affect network traffic and/or systems, devices, etc. in
order to achieve a desired policy state. This (new) policy state
provides one or more (new) behaviors. A policy action ordinarily
changes the portion configuration of one or more elements.

A PolicyRule contains one or more policy actions. A policy
administrator can assign an order to the actions associated with a
PolicyRule, complete with an indication of whether the range that falls on indicated order
is mandatory, recommended, or of no significance. Ordering of the selected day. For example, if
actions associated with a PolicyRule is accomplished via a property in
the range
extends from 2100 until 0800, ActionInPolicyRule aggregation.

The actions associated with a PolicyRule are executed if and only if
the day overall condition(s) of week mask selects Monday
and Tuesday, then the policy is active during the following three
intervals:

From midnight Sunday until 0800 Monday;
From 2100 Monday until 0800 Tuesday;
From 2100 Tuesday until 21:59:59 Tuesday. PolicyRule evaluates to TRUE.

The property class definition of PolicyAction is as follows:

NAME TimeOfDayMask PolicyAction
DESCRIPTION A class representing a rule-specific or reusable
policy action to be performed if the condition for
a policy rule evaluates to TRUE.
DERIVED FROM Policy
ABSTRACT FALSE
PROPERTIES SystemCreationClassName[key]

Moore, et al. Expires: Oct 1999 + 6 months [Page 34] 44]

Internet Draft Policy Core Information Model October 1999

DESCRIPTION The range of times at which a policy rule is valid.
If the second time is earlier than the first, then
the interval spans midnight.
SYNTAX string
FORMAT hhmmss:hhmmss

6.5.6.

SystemName[key]
PolicyRuleCreationClassName[key]
PolicyRuleName[key]
CreationClassName[key]
PolicyActionName[key]

6.7.1. The Key Property "ApplicableTimeZone" "SystemCreationClassName"

This property is used helps to explicitly define a time zone for use by the
TimePeriod and identify the various Mask properties. If System object in whose scope this
instance of PolicyAction exists. For a rule-specific policy action,
this property is not
present, then local time (at the location where the PolicyRule is
enforced -- system in other words, at whose context the Policy Enforcement Point) is
assumed.

This property specifies time in UTC, using an offset indicator. The
UTC offset indicator policy rule is either defined. For a 'Z', indicating UTC, or
reusable policy action, this is the instance of PolicyRepository
(which is a substring subclass of System) that holds the following form:

'+' or '-' direction from UTC: '+' = east, '-' = west

hh hours from UTC (00..13)

mm minutes policy action.

Note that this property, and the analogous property SystemName, do not
represent propagated keys from UTC (00..59)

For example, an instance of the string "+0200" indicates class System. (If
they did, they would be written with a time zone two hours east dot: System.CreationClassName,
System.Name.) Instead, they are properties defined in the context of UTC, and
this class, which repeat the string "-0830" indicates a time zone 8.5 hours west values from the instance of
UTC.

The System to
which the instance containing them is related, either directly via the
ActionInPolicyRepository aggregation or indirectly via the
ActionInPolicyRule aggregation. See Section 5.3.3 for more on this
topic.

This property definition is defined as follows:

NAME ApplicableTimeZone SystemCreationClassName
DESCRIPTION The time zone for name of the PolicyTimePeriodCondition. class or the subclass used in the
creation of the System object in whose scope this
policy action is defined.
SYNTAX string
FORMAT either 'Z' (UTC) or <'+'|'-'><hhmm>

6.6. The Class "VendorPolicyCondition"
QUALIFIER key

6.7.2. The purpose Key Property "SystemName"

This property completes the identification of the System object in
whose scope this class is to provide instance of PolicyAction exists. For a general escape mechanism for
representing rule-specific
policy conditions that have not been modeled with
specific properties. Instead, the two properties Constraint and
ConstraintEncoding are used to define action, this is the content and format of system in whose context the
condition, as explained below.

As its name suggests, policy rule is
defined. For a reusable policy action, this class is intended for vendor-specific
extensions to the Policy Core Information Model. Standardized
extensions are not expected to use this class.

The class definition instance of
PolicyRepository (which is as follows:

NAME VendorPolicyCondition
DESCRIPTION A class that defines a registered means to describe a subclass of System) that holds the policy
action.

This property is defined as follows:

NAME SystemName
DESCRIPTION The name of the System object in whose scope this
policy condition. action is defined.
SYNTAX string
QUALIFIER key

Moore, et al. Expires: Oct 1999 + 6 months [Page 35] 45]

Internet Draft Policy Core Information Model October 1999

DERIVED FROM PolicyCondition
ABSTRACT FALSE
PROPERTIES Constraint[ ]
ConstraintEncoding

6.6.1.

6.7.3. The Multi-valued Key Property "Constraint"

This property provides "PolicyRuleCreationClassName"

For a general escape mechanism for representing rule-specific policy conditions that have not been modeled with specific properties.
The format of the octet strings in the array is left unspecified in action, this definition. It is determined by the OID value stored in the property ConstraintEncoding. Since ConstraintEncoding is single-
valued, all helps to identify the values
policy rule in whose scope this instance of Constraint share the same format and
semantics.

NOTE: In version 2.2 PolicyAction exists. For
a reusable policy action, this property returns a special value, "No
Rule", indicating that this instance of the CIM model [7], there PolicyAction is no way to
represent an array of octet strings. (A single octet string can be
represented as an ordered array of uint8's, but this does not work for
multi-valued properties where each value is an octet string.) Options
for adding this capability unique to CIM are currently being discussed;
candidates include a new octetString data type, and an embedded object
of class OctetString.
one policy rule.

This document expresses the Constraint property
in terms of a data type "octetString", but this should be interpreted is defined as follows:

NAME PolicyRuleCreationClassName
DESCRIPTION For a placeholder for whatever mechanism the DMTF ultimately agrees
upon.

A rule-specific policy decision point can readily determine whether it supports action, this property
identifies the
values stored class of the policy rule instance in an
whose scope this instance of PolicyAction exists.
For a reusable policy action, this property returns
a special value, "No Rule", indicating that this
instance of Constraint by checking the OID value
from ConstraintEncoding against PolicyAction is not unique to one
policy rule.

SYNTAX string[MaxLen 256]
QUALIFIER key

6.7.4. The Key Property "PolicyRuleName"

For a rule-specific policy action, this property completes the set
identification of OIDs it recognizes. The
action for the policy decision point to take rule in case it does not
recognize the format of whose scope this data could itself be modeled as instance of
PolicyCondition exists. For a reusable policy
rule, governing the behavior action, this property
returns a special value, "No Rule", indicating that this instance of the
PolicyCondition is not unique to one policy decision point.

The rule.

This property is defined as follows:

NAME Constraint PolicyRuleName
DESCRIPTION Escape mechanism for representing constraints that
have not been modeled as specific properties. The
format For a rule-specific policy action, the name of the values
PolicyRule object with which this action is identified by the OID
stored in the property ConstraintEncoding.
associated. For a reusable policy action, a
special value, "No Rule", indicating that this
action is reusable.
SYNTAX octetString

6.6.2. string
QUALIFIER key

6.7.5. The Key Property "ConstraintEncoding" "CreationClassName"

This property identifies the encoding and semantics of the Constraint
property values class or subclass used in the creation of
this instance.

NAME CreationClassName
DESCRIPTION The value name of the class or subclass used in the
creation of this property is a
single string, representing a single OID.

The property is defined as follows:

NAME ConstraintEncoding instance.
SYNTAX string[MaxLen 256]
QUALIFIER key

Moore, et al. Expires: Oct 1999 + 6 months [Page 36] 46]

Internet Draft Policy Core Information Model October 1999

DESCRIPTION An OID encoded as

6.7.6. The Key Property "PolicyActionName"

This property provides a string, identifying the format
and semantics user-friendly name for a policy action, and
is normally what will be displayed to the end-user as the instance
name. It is defined as follows:

NAME PolicyActionName
DESCRIPTION The user-friendly name of this instance's Constraint
property. policy action.
SYNTAX string
QUALIFIER OID

6.7. key

6.8. The Class "PolicyAction" "VendorPolicyAction"

The purpose of a policy action this class is to execute one or more operations
that will affect network traffic and/or systems, devices, etc. in
order to achieve provide a desired policy state. This (new) policy state
provides one or more (new) behaviors. A policy action ordinarily
changes the configuration of one or more elements.

A PolicyRule contains one or more policy actions. A general escape mechanism for
representing policy
administrator can assign an order to the actions associated with a
PolicyRule, complete that have not been modeled with an indication of whether specific
properties. Instead, the indicated order
is mandatory, recommended, or of no significance. Ordering two properties ActionData and ActionEncoding
are used to define the content and format of the
actions associated with a PolicyRule action, as explained
below.

As its name suggests, this class is accomplished via a property in intended for vendor-specific
extensions to the ActionInPolicyRule aggregation.

The actions associated with a PolicyRule Policy Core Information Model. Standardized
extensions are executed if and only if
the overall condition(s) of the PolicyRule evaluates not expected to TRUE. use this class.

The class definition of PolicyAction is as follows:

NAME PolicyAction VendorPolicyAction
DESCRIPTION A class representing that defines a rule-specific or reusable
policy action registered means to be performed if the condition for describe
a policy rule evaluates to TRUE. action.
DERIVED FROM Policy PolicyAction
ABSTRACT FALSE
PROPERTIES SystemCreationClassName[key]
SystemName[key]
PolicyRuleName[key]
PolicyActionName[key]

6.7.1. ActionData[ ]
ActionEncoding

6.8.1. The Key Multi-valued Property "SystemCreationClassName" "ActionData"

This property helps to identify the System object in whose scope this
instance provides a general escape mechanism for representing
policy actions that have not been modeled with specific properties.
The format of PolicyAction exists. For a rule-specific policy action,
this is the system octet strings in whose context the policy rule array is defined. For a
reusable policy action, left unspecified in
this definition. It is determined by the instance of PolicyRepository
(which OID value stored in the
property ActionEncoding. Since ActionEncoding is a subclass single-valued, all
the values of System) that holds ActionData share the policy action.

Note that this property, same format and semantics.

NOTE: In version 2.2 of the analogous property SystemName, do not CIM model [7], there is no direct way to
represent propagated keys from an instance array of the class System. (If
they did, they would octet strings. (A single octet string can be written with a dot: System.CreationClassName,
System.Name.) Instead, they are
represented as an ordered array of uint8's, but this does not work for
multi-valued properties defined in where each value is an octet string.) CIM
has, however, a mechanism that is essentially equivalent to SMI's
(SNMP's) Textual Convention, for refining the context syntax and/or semantics
of existing data types. Using this class, which repeat the values from the instance mechanism, a representation of System to
which the instance containing them is related, either directly via the
octet strings as character strings (specifically, strings consisting

Moore, et al. Expires: Oct 1999 + 6 months [Page 37] 47]

Internet Draft Policy Core Information Model October 1999

ActionInPolicyRepository aggregation or indirectly via

of an even number of the characters A-F and 0-9) has been defined. In
a future version of CIM, though, it is likely that an actual
octetString data type will be added.

A policy decision point can readily determine whether it supports the
values stored in an instance of ActionData by checking the OID value
from ActionEncoding against the set of OIDs it recognizes. The action
for the policy decision point to take in case it does not recognize
the
ActionInPolicyRule aggregation. See Section 5.2.2 for more on format of this
topic.

This data could itself be modeled as a policy rule,
governing the behavior of the policy decision point.

The property is defined as follows:

NAME SystemCreationClassName ActionData
DESCRIPTION Escape mechanism for representing actions that have
not been modeled as specific properties. The name format
of the class or values is identified by the subclass used OID stored in
the
creation of the System object in whose scope this
policy action is defined. property ActionEncoding.
SYNTAX string
QUALIFIER key

6.7.2. uint8

6.8.2. The Key Property "SystemName" "ActionEncoding"

This property completes identifies the identification encoding and semantics of the System object ActionData
property values in
whose scope this instance instance. The value of PolicyAction exists. For a rule-specific
policy action, this property is the system in whose context the policy rule is
defined. For a reusable policy action, this is the instance of
PolicyRepository (which is
single string, representing a subclass of System) that holds the policy
action.

This single OID.

The property is defined as follows:

NAME SystemName ActionEncoding
DESCRIPTION The name of An OID encoded as a string, identifying the System object in whose scope format
and semantics for this
policy action is defined. instance's ActionData
property.
SYNTAX string
QUALIFIER key

6.7.3. OID

6.9. The Key Property "PolicyRuleName"

For a rule-specific policy action, this property identifies the policy
rule in whose scope this instance of PolicyAction exists. For a
reusable policy action, this property returns a special value, the
zero-length string (""), indicating that this instance Class "PolicyRepository"

The class definition of PolicyAction
is not unique to one policy rule.

This property PolicyRepository is defined as follows:

NAME PolicyRuleName PolicyRepository
DESCRIPTION For a rule-specific policy action, the name of the
PolicyRule object with which this action is
associated. For a A class representing an administratively defined
container for reusable policy action, a
special value, policy-related information.
This class does not introduce any additional
properties beyond those in its superclass
AdminDomain, other than the zero-length string (""),
indicating that this action is reusable.
SYNTAX string
QUALIFIER key properties
necessary to make it instantiable. It does,
however, participate in a number of unique
associations.
DERIVED FROM AdminDomain
ABSTRACT FALSE
PROPERTIES CreationClassName[key]

Moore, et al. Expires: Oct 1999 + 6 months [Page 38] 48]

Internet Draft Policy Core Information Model October 1999

6.7.4.

PolicyRepositoryName[key]

6.9.1. The Key Property "PolicyActionName" "CreationClassName"

This property identifies the class or subclass used in the creation of
this instance.

NAME CreationClassName
DESCRIPTION The name of the class or subclass used in the
creation of this instance.
SYNTAX string[MaxLen 256]
QUALIFIER key

6.9.2. The Key Property "PolicyRepositoryName"

This property provides a user-friendly name for a policy action, repository,
and is normally what will be displayed to the end-user as the instance
name. It is defined as follows:

NAME PolicyActionName PolicyRepositoryName
DESCRIPTION The user-friendly name of this policy action.
SYNTAX string
QUALIFIER key

6.8. The Class "VendorPolicyAction"

The purpose of this class is to provide a general escape mechanism for
representing policy actions that have not been modeled with specific
properties. Instead, the two properties ActionData and ActionEncoding
are used to define the content and format of the action, as explained
below.

As its name suggests, this class is intended for vendor-specific
extensions to the Policy Core Information Model. Standardized
extensions are not expected to use this class.

The class definition is as follows:

NAME VendorPolicyAction
DESCRIPTION A class that defines a registered means to describe
a policy action.
DERIVED FROM PolicyAction
ABSTRACT FALSE
PROPERTIES ActionData[ ]
ActionEncoding

6.8.1. The Multi-valued Property "ActionData"

This property provides a general escape mechanism for representing
policy actions that have not been modeled with specific properties.
The format of the octet strings in the array is left unspecified in of this definition. policy repository.
SYNTAX string
QUALIFIER key

6.10. The Class "ResourceManagerCollection"

This class is an abstraction representing a collection of individual
resource managers to which a common set of policies are applied. It
is determined by the OID value stored manifestation in the
property ActionEncoding. Since ActionEncoding is single-valued, all
the values Core Model of ActionData share the same format and semantics.

NOTE: In version 2.2 concept of the CIM model [7], there policy role
discussed in reference [11].

The class definition of ResourceManagerCollection is no way to
represent an array as follows:

NAME ResourceManagerCollection
DESCRIPTION A class representing a collection of octet strings. (A single octet string resource
managers, brought together so that they can be
represented
treated as an ordered array of uint8's, but this does not work for
multi-valued properties where each value is an octet string.) Options
for adding this capability to CIM are currently being discussed;
candidates include a new octetString data type, and an embedded object unit for the purposes of class OctetString. defining and
updating policies.
DERIVED FROM Collection
ABSTRACT FALSE
PROPERTIES CreationClassName[key]
ResourceManagerCollectionName[key]
ResourceManagerType[ ]

6.10.1. The Key Property "CreationClassName"

This document expresses the ActionData property identifies the class or subclass used in terms the creation of a data type "octetString", but
this should be interpreted
as a placeholder for whatever mechanism the DMTF ultimately agrees
upon. instance.

NAME CreationClassName

Moore, et al. Expires: Oct 1999 + 6 months [Page 39] 49]

Internet Draft Policy Core Information Model October 1999

A policy decision point can readily determine whether it supports the
values stored in an instance

DESCRIPTION The name of ActionData by checking the OID value
from ActionEncoding against class or subclass used in the set
creation of OIDs it recognizes. this instance.
SYNTAX string[MaxLen 256]
QUALIFIER key

6.10.2. The action Key Property "ResourceManagerCollectionName"

This property provides a user-friendly name for the policy decision point to take in case it does not recognize
the format a collection that
aggregates a number of this data could itself resource managers; it is normally what will be modeled as a policy rule,
governing
displayed to the behavior of end-user as the policy decision point.

The property instance name. It is defined as
follows:

NAME ActionData ResourceManagerCollectionName
DESCRIPTION Escape mechanism for representing actions that have
not been modeled as specific properties. The format user-friendly name of the values is identified by the OID stored in
the property ActionEncoding. this collection.
SYNTAX uint8

6.8.2. string
QUALIFIER key

6.10.3. The Multi-valued Property "ActionEncoding" "ResourceManagerType"

This property identifies the encoding and semantics provides a set of strings for identifying the ActionData
property values in this instance. The value different
types of this property is resource managers present in a
single string, representing policy domain. Each of these
strings identifies a single OID. policy role.

The property definition is defined as follows:

NAME ActionEncoding ResourceManagerType
DESCRIPTION An OID encoded as a string, identifying the format
and semantics for this instance's ActionData
property. A set of strings to identify policy roles.
SYNTAX string
QUALIFIER OID

6.9. The Class "PolicyRepository"

The class definition

While it isn't part of PolicyRepository the Core Policy Model per se, there is as follows:

NAME PolicyRepository
DESCRIPTION A class representing an administratively defined
container for reusable policy-related information.
This class does not introduce any additional
properties beyond those also a
ResourceManagerType property in its superclass
AdminDomain. It does, the class CIM_Service. (Actually,
this isn't true yet: there is, however, participate in a
number proposal currently before
the DMTF to add this property to CIM_Service.) Individual resource
managers are modeled as instances of unique associations.
DERIVED FROM AdminDomain
ABSTRACT FALSE CIM_Service, so this property in
CIM_Service identifies the roles that a resource manager plays.

7. Association and Aggregation Definitions

The first three subsections of this section introduce relationships,
associations, and aggregations as they are used in CIM. The remaining

Moore, et al. Expires: Oct 1999 + 6 months [Page 40]

Internet Draft Policy Core Information Model October 1999
subsections present the class definitions for the associations and
aggregations that are part of the Policy Core Information Model.

7.1. Relationships

Relationships are a central feature of information models. A
relationship represents a physical or conceptual connection between
objects. CIM and DEN define the general concept of an association
between two (or more) objects. Two types of relationships in CIM are
aggregations (which express whole-part relationships) and

Moore, et al. Expires: Oct 1999 + 6 months [Page 50]

Internet Draft Policy Core Information Model October 1999

associations, such as those that express dependency. Both are
represented as classes, and both are used in this model.

7.2. Associations

An association is a class that contains two or more references, where
each reference identifies another object. An association is defined
using a class. Associations can be defined between classes without
affecting any of the related classes. That is, addition of an
association does not affect the interface of the related classes.

7.3. Aggregations

An aggregation is a strong form of an association. An aggregation is
usually used to represent a "whole-part" relationship. This type of
relationship defines the containment relationship between a system and
the components that make up the system. Aggregation often implies,
but does not require, that the aggregated objects have mutual
dependencies.

7.4. The Aggregation "PolicyGroupInPolicyGroup"

The PolicyGroupInPolicyGroup aggregation enables policy groups to be
nested. This is critical for scalability and manageability, as it
enables complex policies to be constructed from multiple simpler
policies for administrative convenience. For example, a policy group
representing policies for the US might have nested within it policy
groups for the Eastern and Western US.

A PolicyGroup may aggregate other PolicyGroups via this aggregation,
or it may aggregate PolicyRules via the PolicyRuleInPolicyGroup
aggregation. But a single PolicyGroup SHALL NOT do both.

The class definition for the aggregation is as follows:

NAME PolicyGroupInPolicyGroup
DESCRIPTION A class representing the aggregation of
PolicyGroups by a higher-level PolicyGroup.
DERIVED FROM Top PolicyGroup.
ABSTRACT FALSE
PROPERTIES ContainingGroup[ref PolicyGroup[0..n]]
ContainedGroup[ref PolicyGroup[0..n]]

Moore, et al. Expires: Oct 1999 + 6 months [Page 41]

Internet Draft Policy Core Information Model October 1999

7.4.1. The Reference "ContainingGroup"

This property contains the name of a PolicyGroup that contains one or
more other PolicyGroups. Note that for any single instance of the
association class PolicyGroupInPolicyGroup, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that there may be 0, 1, or more than one PolicyGroups that
contain any given PolicyGroup.

Moore, et al. Expires: Oct 1999 + 6 months [Page 51]

Internet Draft Policy Core Information Model October 1999

7.4.2. The Reference "ContainedGroup"

This property contains the name of a PolicyGroup contained by one or
more other PolicyGroups. Note that for any single instance of the
association class PolicyGroupInPolicyGroup, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that a given PolicyGroup may contain 0, 1, or more than one
other PolicyGroups.

7.5. The Aggregation "PolicyRuleInPolicyGroup"

A policy group may aggregate one or more policy rules, via the
PolicyRuleInPolicyGroup aggregation. Grouping of policy rules into a
policy group is again for administrative convenience; a policy rule
may also be used by itself, without belonging to a policy group.

A PolicyGroup may aggregate PolicyRules via this aggregation, or it
may aggregate other PolicyGroups via the PolicyGroupInPolicyGroup
aggregation. But a single PolicyGroup SHALL NOT do both.

The class definition for the aggregation is as follows:

NAME PolicyRuleInPolicyGroup
DESCRIPTION A class representing the aggregation of PolicyRules
by a PolicyGroup.
DERIVED FROM Top
ABSTRACT FALSE
PROPERTIES ContainingGroup[ref PolicyGroup[0..n]]
ContainedRule[ref PolicyRule[0..n]]

7.5.1. The Reference "ContainingGroup"

This property contains the name of a PolicyGroup that contains one or
more PolicyRules. Note that for any single instance of the
association class PolicyRuleInPolicyGroup, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that there may be 0, 1, or more than one PolicyGroups that
contain any given PolicyRule.

Moore, et al. Expires: Oct 1999 + 6 months [Page 42]

Internet Draft Policy Core Information Model October 1999

7.5.2. The Reference "ContainedRule"

This property contains the name of a PolicyRule contained by one or
more PolicyGroups. Note that for any single instance of the
association class PolicyRuleInPolicyGroup, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that a given PolicyGroup may contain 0, 1, or more than one
PolicyRules.

7.6. The Aggregation "ConditionInPolicyRule"

A policy rule aggregates zero or more instances of the PolicyCondition
class, via the ConditionInPolicyRule association. A policy rule that
aggregates zero policy conditions is not a valid rule -- it may, for

Moore, et al. Expires: Oct 1999 + 6 months [Page 52]

Internet Draft Policy Core Information Model October 1999

example, be in the process of being entered into the policy
repository. A policy rule has no effect until it is valid. The
conditions aggregated by a policy rule are grouped into two levels of
lists: either an ORed set of ANDed sets of conditions (DNF, the
default) or an ANDed set of ORed sets of conditions (CNF). Individual
conditions in these lists may be negated. The property
ConditionListType specifies which of these two grouping schemes
applies to a particular PolicyRule.

Since conditions may be defined explicitly in a subclass of
PolicyRule, the AND/OR mechanism to combine these conditions with
other (associated) PolicyConditions MUST be specified by the
PolicyRule's subclass.

In either case, the conditions are used to determine whether to
perform the actions associated with the PolicyRule.

One or more policy time periods may be among the conditions associated
with a policy rule via the ConditionInPolicyRule association. In this
case, the time periods are simply additional conditions to be
evaluated along with any other conditions specified for the rule.

The class definition for the aggregation is as follows:

NAME ConditionInPolicyRule
DESCRIPTION A class representing the aggregation of
PolicyConditions by a PolicyRule.
DERIVED FROM Top
ABSTRACT FALSE
PROPERTIES ContainingRule[ref PolicyRule[0..n]]
ContainedCondition[ref PolicyCondition[0..n]]
GroupNumber
ConditionNegated

7.6.1. The Reference "ContainingRule"

This property contains the name of a PolicyRule that contains one or
more PolicyConditions. Note that for any single instance of the

Moore, et al. Expires: Oct 1999 + 6 months [Page 43]

Internet Draft Policy Core Information Model October 1999
association class ConditionInPolicyRule, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that there may be 0, 1, or more than one PolicyRules that
contain any given PolicyCondition.

7.6.2. The Reference "ContainedCondition"

This property contains the name of a PolicyCondition contained by one
or more PolicyRules. Note that for any single instance of the
association class ConditionInPolicyRule, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that a given PolicyRule may contain 0, 1, or more than one
PolicyConditions.

Moore, et al. Expires: Oct 1999 + 6 months [Page 53]

Internet Draft Policy Core Information Model October 1999

7.6.3. The Property "GroupNumber"

This property contains an integer identifying the group to which the
condition referenced by the ContainedCondition property is assigned in
forming the overall conditional expression for the policy rule
identified by the ContainingRule reference.

The property is defined as follows:

NAME GroupNumber
DESCRIPTION Unsigned integer indicating the group to which the
condition identified by the ContainedCondition
property is to be assigned.
SYNTAX uint16

7.6.4. The Property "ConditionNegated"

This property is a boolean, indicating whether the condition
referenced by the ContainedCondition property is negated in forming
the overall conditional expression for the policy rule identified by
the ContainingRule reference.

The property is defined as follows:

NAME ConditionNegated
DESCRIPTION Indication follows:

NAME ConditionNegated
DESCRIPTION Indication of whether the condition identified by
the ContainedCondition property is negated. (TRUE
indicates that the condition IS negated, FALSE
indicates that it IS NOT negated.)
SYNTAX boolean

7.7. The Association "ConditionSubject"

This association represents a condition that identifies the subject
requesting a service that has its access controlled by a policy rule.
A subject might, for example, request access to a particular system,
or to a particular resource (file, printer, etc.) associated with a
system.

In networking cases, a subject is ordinarily identified by the origin
address information in the packet that causes a policy rule to be
evaluated. Thus some component of the Policy Framework must resolve
the object reference present in this association into a lower-level
condition against which an origin address can be tested. The
component that performs this resolution is typically, but not
necessarily, the Policy Consumer.

The resolution itself may be minimal, since in some cases the object
being referred to will have an address, address range, or subnet as
one of whether the condition identified by
the ContainedCondition property is negated. (TRUE
indicates that its properties. In other cases, though, the condition IS negated, FALSE
indicates that it IS NOT negated.)
SYNTAX boolean object may

Moore, et al. Expires: Oct 1999 + 6 months [Page 44] 54]

Internet Draft Policy Core Information Model October 1999

7.7. The Aggregation "PolicyRuleValidityPeriod"

A different relationship between a policy rule and

identify a policy time
period is represented subject only by the PolicyRuleValidityPeriod association:
scheduled activation and deactivation of the policy rule. If a policy
rule is associated with multiple policy time periods via this
association, then the rule is active if at least one of the time
periods indicates that it is active. (In name, in which case other words, the time
periods are ORed to determine whether the rule is active.) A policy
time period may information
correlating names with network addresses must be aggregated by multiple policy rules. A rule that
does not point used to a policy time period via this association is, from perform the point of view of scheduling, always active. It may, however, be
inactive for other reasons.

Time periods are a general concept that can be used in other
applications. However, they are mentioned explicitly here in this
specification since they are frequently used in policy applications.
resolution.

The class definition for the aggregation association is as follows:

NAME PolicyRuleValidityPeriod ConditionSubject
DESCRIPTION A class representing indicating that a ManagedElement plays the aggregation of
PolicyTimePeriodConditions by
subject role for a PolicyRule.
DERIVED FROM Top policy condition.
ABSTRACT FALSE
PROPERTIES ContainingRule[ref PolicyRule[0..n]]
ContainedPtp[ref PolicyTimePeriodCondition[0..n]] Subject[ref ManagedElement[0..n]]
Condition[ref PolicyCondition[0..n]]

7.7.1. The Reference "ContainingRule" "Subject"

This property contains the name of a PolicyRule ManagedElement that contains plays the
subject role for one or more PolicyTimePeriodConditions. PolicyConditions. Note that for any
single instance of the association class PolicyRuleValidityPeriod, ConditionSubject, this
property (like all Reference properties) is single-valued. The [0..n]
cardinality indicates that there a given ManagedElement may be play the subject
role for 0, 1, or more than one PolicyRules that
contain any given PolicyTimePeriodCondition. PolicyConditions.

7.7.2. The Reference "ContainedPtp" "Condition"

This property contains the name of a PolicyTimePeriodCondition
contained by a PolicyCondition related to one or
more PolicyRules. subjects. Note that for any single instance of the association
class PolicyRuleValidityPeriod, ConditionSubject, this property (like all Reference properties)
is single-valued. The [0..n] cardinality indicates that a given PolicyRule
PolicyCondition may contain be associated with 0, 1, or more than one PolicyTimePeriodConditions.
ManagedElements that play the subject role for the condition.

7.8. The Aggregation "ActionInPolicyRule"

A policy rule may aggregate zero or more Association "ConditionTarget"

This association represents a condition that identifies the target of
a requested service whose access is controlled by a policy actions. rule. A
target might, for example, be a particular system to which a subject
is requesting access, or a particular resource (file, printer, etc.)
associated with a system.

In networking cases, a target is ordinarily identified by the
destination address information in the packet that causes a policy
rule to be evaluated. Thus some component of the Policy Framework
must resolve the object reference present in this association into a
lower-level condition against which a destination address can be
tested. The component that aggregates zero policy actions performs this resolution is typically, but
not a valid rule -- it
may, for example, necessarily, the Policy Consumer.

The resolution itself may be minimal, since in some cases the process of object
being entered into referred to will have an address, address range, or subnet as
one of its properties. In other cases, though, the policy object may
identify a target only by name, in which case other information

Moore, et al. Expires: Oct 1999 + 6 months [Page 45] 55]

Internet Draft Policy Core Information Model October 1999

repository. A policy rule has no effect until it is valid. The
actions associated

correlating names with a PolicyRule may be given a required order, a
recommended order, or no order at all. For actions represented as
separate objects, the ActionInPolicyRule aggregation can be used to
express an order. For actions defined explicitly in a subclass of
PolicyRule, the ordering mechanism network addresses must be specified in the subclass
definition.

This aggregation does not indicate whether a specified action order is
required, recommended, or of no significance; the property
SequencedActions in be used to perform the aggregating instance of PolicyRule provides
this indication.
resolution.

The class definition for the aggregation association is as follows:

NAME ActionInPolicyRule ConditionTarget
DESCRIPTION A class representing indicating that a ManagedElement plays the aggregation of
PolicyActions by
target role for a PolicyCondition.
DERIVED FROM Top policy condition.
ABSTRACT FALSE
PROPERTIES ContainingRule[ref PolicyRule[0..n]]
ContainedAction[ref PolicyAction[0..n]]
ActionOrder Target[ref ManagedElement[0..n]]
Condition[ref PolicyCondition[0..n]]

7.8.1. The Reference "ContainingRule" "Target"

This property contains the name of a PolicyRule ManagedElement that contains plays the
target role for one or more PolicyActions. PolicyConditions. Note that for any
single instance of the association class ActionInPolicyRule, ConditionTarget, this
property (like all Reference properties) is single-valued. The [0..n]
cardinality indicates that there a given ManagedElement may be play the target
role for 0, 1, or more than one PolicyRules that
contain any given PolicyAction. PolicyConditions.

7.8.2. The Reference "ContainedAction" "Condition"

This property contains the name of a PolicyAction contained by PolicyCondition related to one or
more PolicyRules. targets. Note that for any single instance of the association
class ActionInPolicyRule, ConditionTarget, this property (like all Reference properties)
is single-valued. The [0..n] cardinality indicates that a given PolicyRule
PolicyCondition may contain be associated with 0, 1, or more than one
PolicyActions.

7.8.3. The Property "ActionOrder"

This property provides an unsigned integer 'n'
ManagedElements that indicates play the
relative position of an action in target role for the sequence condition.

7.9. The Aggregation "PolicyRuleValidityPeriod"

A different relationship between a policy rule and a policy time
period is represented by the PolicyRuleValidityPeriod association:
scheduled activation and deactivation of actions the policy rule. If a policy
rule is associated with a multiple policy rule. When 'n' time periods via this
association, then the rule is a positive integer, it active if at least one of the time
periods indicates that it is active. (In other words, the time
periods are ORed to determine whether the rule is active.) A policy
time period may be aggregated by multiple policy rules. A rule that
does not point to a
place in policy time period via this association is, from
the sequence point of actions to view of scheduling, always active. It may, however, be performed, with smaller
integers indicating earlier positions
inactive for other reasons.

Time periods are a general concept that can be used in the sequence. The special
value '0' indicates "don't care". If two or more actions have the
same non-zero sequence number, other
applications. However, they may be performed are mentioned explicitly here in any order, but this
specification since they are frequently used in policy applications.

The class definition for the aggregation is as follows:

NAME PolicyRuleValidityPeriod

Moore, et al. Expires: Oct 1999 + 6 months [Page 46] 56]

Internet Draft Policy Core Information Model October 1999

they must all be performed at the appropriate place in the overall
action sequence.

DESCRIPTION A series of examples will make ordering of actions clearer:

o If all actions have class representing the same sequence number, regardless aggregation of whether
it is '0' or non-zero, any order is acceptable.

o
PolicyTimePeriodConditions by a PolicyRule.
ABSTRACT FALSE
PROPERTIES ContainingRule[ref PolicyRule[0..n]]
ContainedPtp[ref PolicyTimePeriodCondition[0..n]]

7.9.1. The values

1:ACTION A
2:ACTION B
1:ACTION C
3:ACTION D

indicate two acceptable orders: A,C,B,D or C,A,B,D, since A and C
can be performed in either order, but only at Reference "ContainingRule"

This property contains the '1' position.

o The values

0:ACTION A
2:ACTION B
3:ACTION C
3:ACTION D

require name of a PolicyRule that B,C, and D occur either as B,C,D contains one or as B,D,C. Action
A may appear at any point relative to B,C, and D. Thus the
complete set of acceptable orders is: A,B,C,D; B,A,C,D; B,C,A,D;
B,C,D,A; A,B,D,C; B,A,D,C; B,D,A,C; B,D,C,A.
more PolicyTimePeriodConditions. Note that for any single instance of
the non-zero sequence numbers need not start with '1', and
they need not be consecutive. All that matters is their relative
magnitude.

The association class PolicyRuleValidityPeriod, this property (like
all Reference properties) is defined as follows:

NAME ActionOrder
DESCRIPTION Unsigned integer indicating the relative position
of an action in single-valued. The [0..n] cardinality
indicates that there may be 0, 1, or more than one PolicyRules that
contain any given PolicyTimePeriodCondition.

7.9.2. The Reference "ContainedPtp"

This property contains the sequence name of actions aggregated a PolicyTimePeriodCondition
contained by one or more PolicyRules. Note that for any single
instance of the association class PolicyRuleValidityPeriod, this
property (like all Reference properties) is single-valued. The [0..n]
cardinality indicates that a policy rule.
SYNTAX uint16

7.9. given PolicyRule may contain 0, 1, or
more than one PolicyTimePeriodConditions.

7.10. The Aggregation "ConditionInPolicyRepository" "ActionInPolicyRule"

A reusable policy condition rule may aggregate zero or more policy actions. A policy
rule that aggregates zero policy actions is always related to not a single
PolicyRepository, via valid rule -- it
may, for example, be in the ConditionInPolicyRepository aggregation.
Since, however, process of being entered into the PolicyCondition class represents both reusable and
rule-specific policy conditions, an instance of PolicyCondition (one
that represents
repository. A policy rule has no effect until it is valid. The
actions associated with a rule-specific condition) PolicyRule may not be related given a required order, a
recommended order, or no order at all. For actions represented as
separate objects, the ActionInPolicyRule aggregation can be used to any
policy repository via
express an order. For actions defined explicitly in a subclass of
PolicyRule, the ordering mechanism must be specified in the subclass
definition.

This aggregation does not indicate whether a specified action order is
required, recommended, or of no significance; the property
SequencedActions in the aggregating instance of PolicyRule provides
this aggregation. indication.

The class definition for the aggregation is as follows:

Moore, et al. Expires: Oct 1999 + 6 months [Page 47]

Internet Draft Policy Core Information Model October 1999

NAME ConditionInPolicyRepository ActionInPolicyRule
DESCRIPTION A class representing the aggregation of reusable
PolicyConditions
PolicyActions by a PolicyRepository.
DERIVED FROM Top PolicyCondition.
ABSTRACT FALSE
PROPERTIES ContainingRepository[ref PolicyRepository[0..1]]
ContainedCondition[ref PolicyCondition[0..n]]

7.9.1. ContainingRule[ref PolicyRule[0..n]]
ContainedAction[ref PolicyAction[0..n]]
ActionOrder

Moore, et al. Expires: Oct 1999 + 6 months [Page 57]

Internet Draft Policy Core Information Model October 1999

7.10.1. The Reference "ContainingRepository" "ContainingRule"

This property contains the name of a PolicyRepository containing PolicyRule that contains one or
more PolicyConditions. A reusable PolicyCondition is always
related to exactly one PolicyRepository via the
ConditionInPolicyRepository aggregation. The [0..1] cardinality PolicyActions. Note that for any single instance of the
association class ActionInPolicyRule, this property covers the two types of PolicyConditions: 0 for a rule-
specific PolicyCondition, 1 for a reusable one.

7.9.2. (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that there may be 0, 1, or more than one PolicyRules that
contain any given PolicyAction.

7.10.2. The Reference "ContainedCondition" "ContainedAction"

This property contains the name of a PolicyCondition PolicyAction contained by a
PolicyRepository. one or
more PolicyRules. Note that for any single instance of the
association class ConditionInPolicyRepository, ActionInPolicyRule, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that a given PolicyRepository PolicyRule may contain 0, 1, or more than one PolicyConditions.

7.10.
PolicyActions.

7.10.3. The Aggregation "ActionInPolicyRepository"

A reusable policy Property "ActionOrder"

This property provides an unsigned integer 'n' that indicates the
relative position of an action in the sequence of actions associated
with a policy rule. When 'n' is always related to a single
PolicyRepository, via the ActionInPolicyRepository aggregation.
Since, however, positive integer, it indicates a
place in the PolicyAction class represents both reusable and
rule-specific policy actions, an instance sequence of PolicyAction (one that
represents a rule-specific action) actions to be performed, with smaller
integers indicating earlier positions in the sequence. The special
value '0' indicates "don't care". If two or more actions have the
same non-zero sequence number, they may not be related to performed in any policy
repository via this aggregation.

The class definition for order, but
they must all be performed at the aggregation is as follows:

NAME ActionInPolicyRepository
DESCRIPTION A class representing appropriate place in the aggregation overall
action sequence.

A series of reusable
PolicyActions by a PolicyRepository.
DERIVED FROM Top
ABSTRACT FALSE
PROPERTIES ContainingRepository[ref PolicyRepository[0..1]]
ContainedAction[ref PolicyAction[0..n]]

7.10.1. The Reference "ContainingRepository"

This property contains examples will make ordering of actions clearer:

o If all actions have the name same sequence number, regardless of a PolicyRepository containing one whether
it is '0' or more PolicyActions. A reusable PolicyAction non-zero, any order is always related to
exactly one PolicyRepository via the ActionInPolicyRepository
aggregation. acceptable.

o The [0..1] cardinality for this property covers the values

1:ACTION A
2:ACTION B
1:ACTION C
3:ACTION D

indicate two acceptable orders: A,C,B,D or C,A,B,D, since A and C
can be performed in either order, but only at the '1' position.

o The values

0:ACTION A
2:ACTION B
3:ACTION C

Moore, et al. Expires: Oct 1999 + 6 months [Page 48] 58]

Internet Draft Policy Core Information Model October 1999

types of PolicyActions: 0 for a rule-specific PolicyAction, 1 for a
reusable one.

7.10.2. The Reference "ContainedAction"

This property contains the name of a PolicyAction contained by a
PolicyRepository. Note that for any single instance of the
association class ActionInPolicyRepository, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates

3:ACTION D

require that a given PolicyRepository may contain 0, 1, B,C, and D occur either as B,C,D or more than
one PolicyActions.

7.11. The Weak Aggregation "PolicyGroupInSystem" as B,D,C. Action
A PolicyGroup is named within may appear at any point relative to B,C, and D. Thus the scope
complete set of a CIM System, via acceptable orders is: A,B,C,D; B,A,C,D; B,C,A,D;
B,C,D,A; A,B,D,C; B,A,D,C; B,D,A,C; B,D,C,A.

Note that the weak
aggregation PolicyGroupInSystem. non-zero sequence numbers need not start with '1', and
they need not be consecutive. All that matters is their relative
magnitude.

The class definition for the aggregation property is defined as follows:

NAME PolicyGroupInSystem ActionOrder
DESCRIPTION A class representing Unsigned integer indicating the weak aggregation relative position
of
PolicyGroups by a CIM System.
DERIVED FROM Top
ABSTRACT FALSE
PROPERTIES ContainingSystem[ref System]
ContainedGroup[ref PolicyGroup[weak]]

7.11.1. The Reference "ContainingSystem"

This property contains an action in the name sequence of actions aggregated
by a CIM System that provies a naming
scope for one or more PolicyGroups. Since this is a weak aggregation,
the cardinality for CIM System policy rule.
SYNTAX uint16

7.11. The Association "ConditionInPolicyRepository"

A reusable policy condition is always 1, that is, related to a PolicyGroup is
always named within the scope of exactly one CIM System.

7.11.2. The Reference "ContainedGroup"

This property contains single
PolicyRepository, via the name of a PolicyGroup named within ConditionInPolicyRepository association.
Since, however, the
context of a CIM System. Note that for any single PolicyCondition class represents both reusable and
rule-specific policy conditions, an instance of the
association class PolicyGroupInSystem, this property (like all
Reference properties) is single-valued. The "weak" qualifier, which
is equivalent to a [0..n] cardinality, indicates PolicyCondition (one
that represents a given CIM
System rule-specific condition) may have 0, 1, or more than one PolicyGroups named within its
scope.

7.12. The Weak Aggregation "PolicyRuleInSystem"

Regardless of whether it belongs to a PolicyGroup (or not be related to multiple
PolicyGroups), a PolicyRule is named within the scope of a CIM System, any
policy repository via the weak aggregation PolicyRuleInSystem. this association.

The class definition for the aggregation association is as follows:

Moore, et al. Expires: Oct 1999 + 6 months [Page 49]

Internet Draft Policy Core Information Model October 1999

NAME PolicyRuleInSystem ConditionInPolicyRepository
DESCRIPTION A class representing the weak aggregation inclusion of
PolicyRules by a CIM System.
DERIVED FROM Top reusable
PolicyCondition in a PolicyRepository.
ABSTRACT FALSE
PROPERTIES ContainingSystem[ref System]
ContainedRule[ref PolicyRule[weak]]

7.12.1. ContainingRepository[ref PolicyRepository[0..1]]
ContainedCondition[ref PolicyCondition[0..n]]

7.11.1. The Reference "ContainingSystem" "ContainingRepository"

This property contains the name of a CIM System that provies a naming
scope for PolicyRepository containing one
or more PolicyRules. Since this PolicyConditions. A reusable PolicyCondition is a weak aggregation, always
related to exactly one PolicyRepository via the
ConditionInPolicyRepository association. The [0..1] cardinality for CIM System is always 1, that is, a PolicyRule is
always named within
this property covers the scope two types of exactly one CIM System.

7.12.2. PolicyConditions: 0 for a rule-
specific PolicyCondition, 1 for a reusable one.

7.11.2. The Reference "ContainedRule" "ContainedCondition"

This property contains the name of a PolicyRule named within the
context of PolicyCondition included in a CIM System.
PolicyRepository. Note that for any single instance of the
association class PolicyRuleInSystem, ConditionInPolicyRepository, this property (like all
Reference properties) is single-valued. The "weak" qualifier, which
is equivalent to a [0..n] cardinality, cardinality

Moore, et al. Expires: Oct 1999 + 6 months [Page 59]

Internet Draft Policy Core Information Model October 1999

indicates that a given CIM
System PolicyRepository may have contain 0, 1, or more than
one PolicyRules named within its
scope.

7.13. The Aggregation "PolicyRepositoryInPolicyRepository" PolicyConditions.

7.12. The PolicyRepositoryInPolicyRepository aggregation enables Association "ActionInPolicyRepository"

A reusable policy
repositories action is always related to a single
PolicyRepository, via the ActionInPolicyRepository association.
Since, however, the PolicyAction class represents both reusable and
rule-specific policy actions, an instance of PolicyAction (one that
represents a rule-specific action) may not be nested. related to any policy
repository via this association.

The class definition for the aggregation is as follows:

NAME PolicyRepositoryInPolicyRepository
DESCRIPTION A class representing the aggregation association is as follows:

NAME ActionInPolicyRepository
DESCRIPTION A class representing the inclusion of a reusable
PolicyAction in a PolicyRepository.
ABSTRACT FALSE
PROPERTIES ContainingRepository[ref PolicyRepository[0..1]]
ContainedAction[ref PolicyAction[0..n]]

7.12.1. The Reference "ContainingRepository"

This property contains the name of a PolicyRepository containing one
or more PolicyActions. A reusable PolicyAction is always related to
exactly one PolicyRepository via the ActionInPolicyRepository
association. The [0..1] cardinality for this property covers the two
types of
PolicyRepositories by PolicyActions: 0 for a higher-level
PolicyRepository.
DERIVED FROM Top
ABSTRACT FALSE
PROPERTIES ContainingRepository[ref PolicyRepository[0..n]]
ContainedRepository[ref PolicyRepository[0..n]]

7.13.1. rule-specific PolicyAction, 1 for a
reusable one.

7.12.2. The Reference "ContainingRepository" "ContainedAction"

This property contains the name of a PolicyRepository that contains
one or more other PolicyRepositories. PolicyAction included in a
PolicyRepository. Note that for any single instance of the
association class PolicyRepositoryInPolicyRepository, ActionInPolicyRepository, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that there a given PolicyRepository may be contain 0, 1, or more than
one
PolicyRepositories that contain any given PolicyRepository.

EDITOR'S NOTE: This matches PolicyActions.

7.13. The Weak Association "PolicyGroupInSystem"

A PolicyGroup is named within the recursive aggregation for
PolicyGroups, but I could also see scope of a CIM System, via the weak
association PolicyGroupInSystem. This relationship is an argument association
rather than an aggregation because in CIM a System aggregates
ManagedSystemElements, while the Core Policy classes (that is, the
subclasses of the abstract class Policy) are derived from the CIM
class ManagedElement, not ManagedSystemElement.

The class definition for having the association is as follows:

NAME PolicyGroupInSystem

Moore, et al. Expires: Oct 1999 + 6 months [Page 50] 60]

Internet Draft Policy Core Information Model October 1999

cardinality at the "containing" end being [0..1], which would make
this more like DIT containment. Let's just decide one way or

DESCRIPTION A class representing the
other.

7.13.2. weak association of a
PolicyGroup with a CIM System.
ABSTRACT FALSE
PROPERTIES ContainingSystem[ref System]
ContainedGroup[ref PolicyGroup[weak]]

7.13.1. The Reference "ContainedRepository" "ContainingSystem"

This property contains the name of a PolicyRepository contained by CIM System that provides a naming
scope for one or more other PolicyRepositories [or simply "by another
PolicyRepository" -- see PolicyGroups. Since this is a weak association,
the EDITOR'S NOTE in cardinality for CIM System is always 1, that is, a PolicyGroup is
always named within the scope of exactly one CIM System.

7.13.2. The Reference "ContainedGroup"

This property contains the name of a PolicyGroup named within the preceding section].
context of a CIM System. Note that for any single instance of the
association class
PolicyRepositoryInPolicyRepository, PolicyGroupInSystem, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that a given PolicyRepository CIM System may contain have 0, 1, or more than one other
PolicyRepositories.
PolicyGroups named within its scope.

7.14. The Policy Group Jurisdiction Associations

There are four CIM associations that link objects representing
resources Weak Association "PolicyRuleInSystem"

Regardless of whether it belongs to which policies apply with the a PolicyGroup objects that
represent these policies. The fact that there are four associations (or to multiple
PolicyGroups), a PolicyRule is named within the scope of a CIM System,
via the weak association PolicyRuleInSystem. This relationship is an
association rather than one reflects how an aggregation because in CIM has modeled a System
aggregates ManagedSystemElements, while the resources, not how it
has modeled policies. Since all four associations work in exactly Core Policy classes (that
is, the
same way, this section will focus on only one subclasses of them:
GroupWithSettingJurisdiction. The remaining three associations,
GroupWithMseJurisdiction, GroupWithResponsibleEntityJurisdiction, and
GroupWithCollectionJurisdiction the abstract class Policy) are equivalent to this one. derived from the
CIM class ManagedElement, not ManagedSystemElement.

The class definition for the GroupWithSettingJurisdiction association is as follows:

NAME GroupWithSettingJurisdiction PolicyRuleInSystem
DESCRIPTION A class representing the fact that a PolicyGroup is
applicable to weak association of a resource represented by
PolicyRule with a Setting
object.
DERIVED FROM Top CIM System.
ABSTRACT FALSE
PROPERTIES GroupScope[ref Setting[0..n]]
ApplicableGroup[ref PolicyGroup[0..n]] ContainingSystem[ref System]
ContainedRule[ref PolicyRule[weak]]

7.14.1. The Reference "GroupScope" "ContainingSystem"

This property contains the name of a Setting object to which the
policies represented by CIM System that provides a naming
scope for one or more PolicyRules apply. PolicyRules. Since this is a weak association,
the cardinality for CIM System is always 1, that is, a PolicyRule is
always named within the scope of exactly one CIM System.

7.14.2. The Reference "ContainedRule"

This property contains the name of a PolicyRule named within the
context of a CIM System. Note that for any single instance of the

Moore, et al. Expires: Oct 1999 + 6 months [Page 61]

Internet Draft Policy Core Information Model October 1999

association class
GroupWithSettingJurisdiction, PolicyRuleInSystem, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that
there a given CIM System may be have 0, 1, or more than one Settings
PolicyRules named within its scope.

7.15. The Aggregation "PolicyRepositoryInPolicyRepository"

The PolicyRepositoryInPolicyRepository aggregation enables policy
repositories to which be nested.

The class definition for the policies
belonging to aggregation is as follows:

NAME PolicyRepositoryInPolicyRepository
DESCRIPTION A class representing the aggregation of
PolicyRepositories by a single PolicyGroup apply.

Moore, et al. Expires: Oct 1999 + 6 months [Page 51]

Internet Draft Policy Core Information Model October 1999

7.14.2. higher-level
PolicyRepository.
ABSTRACT FALSE
PROPERTIES ContainingRepository[ref PolicyRepository[0..n]]
ContainedRepository[ref PolicyRepository[0..n]]

7.15.1. The Reference "ApplicableGroup" "ContainingRepository"

This property contains the name of a PolicyGroup whose policies apply
to the resources represented by PolicyRepository that contains
one or more Setting objects. other PolicyRepositories. Note that for any single
instance of the association class
GroupWithSettingJurisdiction, PolicyRepositoryInPolicyRepository,
this property (like all Reference properties) is single-valued. The
[0..n] cardinality indicates that a
given Setting there may be governed by policies belonging to 0, 1, or more than one PolicyGroup.

7.15. The Policy Rule Jurisdiction Associations

There are also four CIM associations that link objects representing
resources to which policies apply directly with the PolicyRule objects
that represent these policies, without going by way of a PolicyGroup.
The fact
PolicyRepositories that there are four associations rather than one reflects how
CIM has modeled the resources, not how it has modeled policies. Since
all four associations work in exactly contain any given PolicyRepository.

EDITOR'S NOTE: This matches the same way, this section will
focus on only one of them: RuleWithSettingJurisdiction. The
remaining three associations, RuleWithMseJurisdiction,
RuleWithResponsibleEntityJurisdiction, and
RuleWithCollectionJurisdiction are equivalent to this one.

The class definition recursive aggregation for
PolicyGroups, but I could also see an argument for having the RuleWithSettingJurisdiction association
is as follows:

NAME RuleWithSettingJurisdiction
DESCRIPTION A class representing
cardinality at the fact that a PolicyRule is
applicable to a resource represented by a Setting
object.
DERIVED FROM Top
ABSTRACT FALSE
PROPERTIES RuleScope[ref Setting[0..n]]
ApplicableRule[ref PolicyRule[0..n]]

7.15.1. "containing" end being [0..1], which would make
this more like DIT containment. Let's just decide one way or the
other.

7.15.2. The Reference "RuleScope" "ContainedRepository"

This property contains the name of a Setting object to which the
policies represented PolicyRepository contained by one
or more PolicyRules apply. other PolicyRepositories [or simply "by another
PolicyRepository" -- see the EDITOR'S NOTE in the preceding section].
Note that for any single instance of the association class
RuleWithSettingJurisdiction,
PolicyRepositoryInPolicyRepository, this property (like all Reference
properties) is single-valued. The [0..n] cardinality indicates that
there a
given PolicyRepository may be contain 0, 1, or more than one Settings other
PolicyRepositories.

7.16. The Association "ResourceManagerCollectionPolicyGroup"

This association relates a set of policies aggregated into a
PolicyGroup to which a ResourceManagerCollection representing one or more
policy roles.

Moore, et al. Expires: Oct 1999 + 6 months [Page 62]

Internet Draft Policy Core Information Model October 1999

The class definition for the policies
belonging association is as follows:

NAME ResourceManagerCollectionPolicyGroup
DESCRIPTION A class representing the applicability of the
PolicyRules (or lower-level PolicyGroups) in a
PolicyGroup to one or more of the roles represented
by a single PolicyRule apply.

7.15.2. collection of resource managers.
ABSTRACT FALSE
PROPERTIES AffectedRMCollection[ref ResourceManagerCollection[0..n]]
ApplicableGroup[ref PolicyGroup[0..n]]

7.17. The Reference "ApplicableRule" Association "ResourceManagerCollectionPolicyRule"

This property contains association relates an individual PolicyRule to a
ResourceManagerCollection representing one or more policy roles.

The class definition for the name association is as follows:

NAME ResourceManagerCollectionPolicyRule
DESCRIPTION A class representing the applicability of a
PolicyRule whose policies apply to one or more of the resources roles represented
by a collection of resource managers.
ABSTRACT FALSE
PROPERTIES AffectedRMCollection[ref ResourceManagerCollection[0..n]]
ApplicableRule[ref PolicyRule[0..n]]

7.18. The Aggregation "MemberResourceManager"

This aggregation ties individual resource managers (represented as
instances of the class CIM_Service) to a ResourceManagerCollection
representing one or more Setting objects. Note policy roles played by the resource managers.
A constraint on this aggregation is that for any single instance the instances of CIM_Service
referred to via the association ResourceManager property must be ones that
represent resource managers.

The class definition for the aggregation is as follows:

NAME MemberResourceManager
DESCRIPTION A class
RuleWithSettingJurisdiction, representing the aggregation of individual
resource managers by a ResourceManagerCollection.
A constraint on this aggregation is that the
instances of CIM_Service referred to via the
ResourceManager property (like all Reference must be ones that
represent resource managers.
DERIVED FROM MemberService
ABSTRACT FALSE
PROPERTIES RMCollection[ref ResourceManagerCollection[0..n]]
ResourceManager[ref CIM_Service[0..n]]

Moore, et al. Expires: Oct 1999 + 6 months [Page 52] 63]

Internet Draft Policy Core Information Model October 1999

properties) is single-valued.

7.19. The [0..n] cardinality indicates that Association "ResourceManagerPolicyGroup"

This association relates a
given Setting may be governed by policies belonging to 0, 1, or more
than one PolicyRule.

7.16. The Policy Repository Jurisdiction Associations

Finally, there are four CIM associations that link objects
representing resources to which policies apply with
PolicyRepositories containing reusable policy objects that embody
these policies. The fact that there are four associations rather than
one reflects how CIM has modeled the resources, not how it has modeled
policies. Since all four associations work in exactly the same way,
this section will focus on only one set of them:
RepositoryWithSettingJurisdiction. The remaining three associations,
RepositoryWithMseJurisdiction,
RepositoryWithResponsibleEntityJurisdiction, and
RepositoryWithCollectionJurisdiction are equivalent policies aggregated into a
PolicyGroup to this one. an individual ResourceManager.

The class definition for the RepositoryWithSettingJurisdiction association is as follows:

NAME RepositoryWithSettingJurisdiction ResourceManagerPolicyGroup
DESCRIPTION A class representing the fact that applicability of the
PolicyRules (or lower-level PolicyGroups) in a
PolicyRepository contains reusable policy objects
applicable
PolicyGroup to a particular resource represented by a Setting
object.
DERIVED FROM Top manager.
ABSTRACT FALSE
PROPERTIES RepositoryScope[ref Setting[0..n]]
ApplicableRepository[ref PolicyRepository[0..n]]

7.16.1. AffectedResourceManager[ref CIM_Service[0..n]]
ApplicableGroup[ref PolicyGroup[0..n]]

7.20. The Reference "RepositoryScope" Association "ResourceManagerPolicyRule"

This property contains the name of a Setting object association relates an individual PolicyRule to which the
policies represented by the reusable policy objects in one or more
PolicyRepositories apply. Note that an individual
ResourceManager

The class definition for any single instance of the association class RepositoryWithSettingJurisdiction, this property
(like all Reference properties) is single-valued. The [0..n]
cardinality indicates that there may be 0, 1, or more than one
Settings to which as follows:

NAME ResourceManagerPolicyRule
DESCRIPTION A class representing the reusable policy objects in applicability of a single
PolicyRule
apply.

7.16.2. to a particular resource manager.
ABSTRACT FALSE
PROPERTIES AffectedResourceManager[ref CIM_Service[0..n]]
ApplicableRule[ref PolicyRule[0..n]]

7.21. The Reference "ApplicableRepository" Association "ResourceManagerManagedResource"

This property contains association completes the name of three-level hierarchy in the resource
manager model by relating a PolicyRepository whose reusable
policy objects apply resource manager to the resources represented by one or more
Setting objects. Note that it
manages.

The class definition for any single instance of the association
class RepositoryWithSettingJurisdiction, this property (like all
Reference properties) is single-valued. The [0..n] cardinality
indicates that as follows:

NAME ResourceManagerManagedResource
DESCRIPTION A class representing the relationship between a given Setting may be governed by policies represented
by reusable policy objects contained in 0, 1, or more than one
PolicyRepository.

Moore, et al. Expires: Oct 1999 + 6 months [Page 53]

Internet Draft Policy Core Information Model October 1999
resource manager and the resources that it manages.
ABSTRACT FALSE
PROPERTIES ManagingResourceManager[ref CIM_Service[0..n]]
ManagedResource[ref CIM_ManagedSystemElement[0..n]]

8. Intellectual Property

The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to pertain
to the implementation or use of the technology described in this
document or the extent to which any license under such rights might or
might not be available; neither does it represent that it has made any

Moore, et al. Expires: Oct 1999 + 6 months [Page 64]

Internet Draft Policy Core Information Model October 1999

effort to identify any such rights. Information on the IETF's
procedures with respect to rights in standards-track and standards-
related documentation can be found in BCP-11.

Copies of claims of rights made available for publication and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this specification
can be obtained from the IETF Secretariat.

The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.

9. Acknowledgements

The Policy Core Information Model in this document is closely based on
the work of the DMTF's Service Level Agreements working group, so
thanks are due to the members of that working group.

10. Security Considerations

o General: The IETF is concerned with standardizing what happens on
the wire. However, many of the security concerns in a policy
system have to do with things that have nothing to do with what
happens on the wire, like logging, how data is stored on the
repository server, etc. These are out-of-scope for IETF
standardization. However, it is necessary to document the
requirements for a secure policy system, in order to show that the
overall policy framework is viable. Our model for documenting
these requirements is based on prior work in the IETF on DNSSEC and
SNMPv3. One of our objectives in the policy work in the IETF is to
not break the known existing security mechanisms, or to make them
less effective, regardless of whether or not these security
mechanisms affect what flows on the wire.

o Users: The first step in identifying security requirements for
policy, is to identify the users of policy. The users fall into
three categories:

Moore, et al. Expires: Oct 1999 + 6 months [Page 54]

Internet Draft Policy Core Information Model October 1999

o Administrators of Schema: This group requires the most stringent
authorization and associated security controls. An improper or
mal-formed change in the design of the policy schema carries with
it the danger of rendering the repository inoperable while the
repository is being repaired or re-built. During this time, the
policy enforcement entities would need to continue to enforce
policies according to their prior configuration. The good news is
that it is expected that large network operators will change schema

Moore, et al. Expires: Oct 1999 + 6 months [Page 65]

Internet Draft Policy Core Information Model October 1999

design infrequently, and, when they do, the schema creation changes
will be tested on an off-line copy of the directory before the
operational directory is updated. Typically, a small group of
schema administrators will be authorized to make these changes in a
service provider or enterprise environment. The ability to
maintain an audit trails trail is also required here.

o Administrators of Schema Content: This group requires authorization
to load values (entries) into a policy repository) schema
(read/write access). An audit trail mechanism is also required
here. The effect of entering improperly formatted or maliciously-
intended data into a policy repository, could potentially result in
re-configuring mass numbers of network elements in a way that
renders them to be inoperable, or of rendering network resources
inaccessible for an extended period of time,

o Applications and Policy Consumers: These entities must be
authorized for read-only access to the policy repository, so that
they may acquire policy for the purposes of passing it to their
respective enforcement entities.

o Security Disciplines:

o Audit Trail (Non-repudiation): In general, standardizing
mechanisms for non-repudiation is outside the scope of the
IETF; however, we can certainly document the need for this
function in systems which maintain and distribute policy. The
dependency for support of this function is on the implementers
of these systems, and not on any specific standards for
implementation. The requirement for a policy system is that a
minimum level of auditing via an auditing facility must be
provided. Logging should be enabled. This working group will
not specify what this minimal auditing function consists of.

o Access Control/Authorization: Access Control List (ACL)
functionality must be provided. The two administrative sets of
users documented above will form the basis for two
administrative use cases which require support.

o Authentication: Authentication support on the order of that
available with TLS and Kerboros are acceptable for
authentication. We advise against using weaker mechanisms,
such as clear text and HTTP Digest. Mutual authentication is
recommended.

Moore, et al. Expires: Oct 1999 + 6 months [Page 55]

Internet Draft Policy Core Information Model October 1999

o Integrity/Privacy: Integrity/privacy support on the order of
TLS or IPSEC is acceptable for encryption and data integrity
on the wire. If physical or virtual access to the policy
repository is in question, it may also be necessary to encrypt
the policy data as it is stored on the file system; however,
specification of mechanisms for this purpose are outside the
scope of this working group. In any case, we recommend that

Moore, et al. Expires: Oct 1999 + 6 months [Page 66]

Internet Draft Policy Core Information Model October 1999

the physical server be located in a physically secure
environment.

In the case of Policy Consumer-to-Policy Target communications, the
use of IPSEC is recommended for providing confidentiality, data
origin authentication, integrity and replay prevention. See
reference [10].

o Denial of Service: We recommend the use of multiple policy
repositories, such that a denial of service attack on any one
repository will not make all policy data inaccessible to legitimate
users. However, this still leaves a denial of service attack
exposure. Our belief is that the use of a policy schema, in a
centrally administered but physically distributed policy
repository, does not increase the risk of denial of service
attacks; however, such attacks are still possible. If executed
successfully, such an attack could prevent Policy Consumers from
accessing a policy repository, and thus prevent them from acquiring
new policy. In such a case, the Policy Consumers, and associated
Policy Targets would continue operating under the policies in force
before the denial of service attack was launched. Note that
exposure of policy systems to denial of service attacks is not any
greater than the exposure of DNS with DNSSEC in place.

11. References

[1] J. Strassner and E. Ellesson, "Terminology for describing network
policy and services", draft-strassner-policy-terms-02.txt, June
1999.

[2] Bhattacharya, P., and R. Adams, W. Dixon, R. Pereira, R. Rajan, "An
LDAP Schema for Configuration and Administration of IPSec based
Virtual Private Networks (VPNs)", Internet-Draft work in progress,
October 1998

[3] Rajan, R., and J. C. Martin, S. Kamat, M. See, R. Chaudhury, D.
Verma, G. Powers, R. Yavatkar, "Schema for Differentiated Services
and Integrated Services in Networks", Internet-Draft work in
progress, October 1998

[4] J. Strassner and S. Judd, "Directory-Enabled Networks", version
3.0c5 (August 1998).

Moore, et al. Expires: Oct 1999 + 6 months [Page 56]

Internet Draft Policy Core Information Model October 1999

[5] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.

[6] Hovey, R., and S. Bradner, "The Organizations Involved in the IETF
Standards Process", BCP 11, RFC 2028, October 1996.

[7] Distributed Management Task Force, Inc., "Common Information Model
(CIM) Specification, version 2.2, June 14, 1999.

Moore, et al. Expires: Oct 1999 + 6 months [Page 67]

Internet Draft Policy Core Information Model October 1999

[8] J. Strassner, policy architecture BOF presentation, 42nd IETF
Meeting, Chicago, Illinois, October, 1998

[9] J. Strassner and E. Ellesson, B. Moore "Policy Framework LDAP Core
Schema," draft-ietf-policy-core-schema-05.txt, October 1999.

[10] R. Yavatkar and D. Pendarakis, R. Guerin, "A Framework for Policy-
based Admission Control", draft-ietf-rap-framework-03.txt, April
1999.

[11] Stevens, M., and W. Weiss, H. Mahon, B. Moore, J. Strassner, G.
Waters, A. Westerinen, J. Wheeler, "Policy Framework", draft-ietf-
policy-framework-00.txt, September, 1999.

12. Authors' Addresses

John Strassner
Cisco Systems, Bldg 1
170 West Tasman Drive
San Jose, CA 95134
Phone: +1 408-527-1069
Fax: +1 408-527-1722
E-mail: johns@cisco.com

Ed Ellesson
IBM Corporation, Corporation/Tivoli, JDGA/501
4205 S. Miami Blvd.
Research Triangle Park, NC 27709
Phone: +1 919-254-4115
Fax: +1 919-254-6243
E-mail: ellesson@raleigh.ibm.com

Bob Moore
IBM Corporation, JDGA/501 BRQA/502
4205 S. Miami Blvd.
Research Triangle Park, NC 27709
Phone: +1 919-254-4436
Fax: +1 919-254-6243
E-mail: remoore@us.ibm.com

13. Full Copyright Statement

This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it

Moore, et al. Expires: Oct 1999 + 6 months [Page 57]

Internet Draft Policy Core Information Model October 1999
or assist in its implementation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing

Moore, et al. Expires: Oct 1999 + 6 months [Page 68]

Internet Draft Policy Core Information Model October 1999

the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of developing
Internet standards in which case the procedures for copyrights defined
in the Internet Standards process must be followed, or as required to
translate it into languages other than English.

The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.

This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT
NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN
WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Moore, et al. Expires: Oct 1999 + 6 months [Page 58] 69]

----