Internet DRAFT - draft-terena-itdwg-iodef-requirements

draft-terena-itdwg-iodef-requirements



INTERNET DRAFT                                          Jimmy Arvidsson 
draft-terena-itdwg-iodef-requirements-00.txt                 Telia CERT 
Category: Informational                                  Andrew Cormack 
                                                             JANET-CERT 
Expires 15 May 2001                                      Yuri Demchenko 
                                                                 TERENA 
                                                             Jan Meijer 
                                                                SURFnet 
                                                      November 15, 2000 
    
    
    
       Incident object Description and Exchange Format Requirements 
              <draft-terena-itdwg-iodef-requirements-00.txt> 
    
    
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 obsolete 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/lid-abstracts.txt 
    
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   Distribution of this memo is unlimited. 
    
   This Internet Draft expires May 13, 2001. 
    
   Copyright Notice 
    
   Copyright (C) The Internet Society (2000). All Rights Reserved. 
    
1. Abstract 
    
   The purpose of the Incident object Description and Exchange Format 
   is to define a common data format for the description, archiving and 
   exchange of information about incidents between CSIRTs (including 
   alert, incident in investigation, archiving, statistics, reporting, 
   etc.). This document describes the high-level requirements for such 
   a description and exchange format, including the reasons for those 

 
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   requirements. Examples are used to illustrate the requirements where 
   necessary. 
    
2. Conventions used in this document 
    
   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 [1]. 
    
3. Introduction 
    
   This document defines requirements for the Incident object 
   Description and Exchange Format (IODEF), which is the intended 
   product of the Incident Taxonomy Working Group (ITDWG) at TERENA 
   [2]. IODEF is planned to be a standard format which allows CSIRTs to 
   exchange operational and statistical information; it may also 
   provide a basis for the development of compatible and inter-operable 
   tools for Incident recording, tracking and exchange. 
    
   Another aim is to extend the work of IETF IDWG (currently focused on 
   Intrusion Detection exchange format and communication protocol) to 
   the description of incidents as higher level elements in Network 
   Security. This will involve CSIRTs and their constituency related 
   issues.  
    
   The IODEF set of documents of which the current document is the 
   first will contain IODEF Data Model and XML DTD specification. 
    
   Current version of the draft represent work in progress and will be 
   updated both in the frame of IETF procedure and in the frame of 
   ITDWG at TERENA. Further discussion of this document will take place 
   in the ITDWG mailing lists <incident-taxonomy@terena.nl> or 
   <iodef@terena.nl>, archives are available correspondently at 
   http://hypermail.terena.nl/incident-taxonomy-list/mail-archive/ and 
   http://hypermail.terena.nl/iodef-list/mail-archive/ 
    
    
3.1. Rationale 
    
   This work is based on attempts to establish cooperation and 
   information exchange between leading/advanced CSIRTs in Europe and 
   among the FIRST community. These CSIRTs understand the advantages of 
   information exchange and cooperation in processing, tracking and 
   investigating security incidents.  
    
   Computer Incidents are becoming distributed and International and 
   involve many CSIRTs across borders, languages and cultures. Post-
   Incident information and statistics exchange is important for future 
   Incident prevention and Internet security improvement. The key 
   element for information exchange in all these cases is a common 
   format for Incident (Object) description. 
    
   It is probable that in further development or implementation the 
   IODEF might be used for forensic purposes, and this means that 

 
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   Incident description must be unambiguous and allow for future 
   custody (archiving/documentation) features. 
    
   Another issue that is targeted by developing IODEF is a need to have 
   higher level Incident description and exchange format than will be 
   provided by IDS (Intrusion Detection Systems) and the proposed IDEF 
   (Intrusion Detection Exchange Format). Compatibility with IDEF and 
   other related standards will be satisfied by the IODEF requirement 
   on modularity and extensibility. IODEF should vertically be 
   compatible with IDEF, IODEF might be able to include or reference 
   IDEF Alert message as initial information about Incident. 
    
3.2. Incident Description Terms 
    
   A definition of the main terms used in the rest of document is given 
   for clarity. 
    
   Where possible, existing definitions will be used; some definitions 
   will need additional detail and further consideration. 
    
   3.2.1. Attack 
    
   An assault on system security that derives from an intelligent 
   threat, i.e., an intelligent act that is a deliberate attempt 
   (especially in the sense of a method or technique) to evade security 
   services and violate the security policy of a system. 
   Attack can be active or passive, by insider or by outsider, or via 
   attack mediator. 
    
   3.2.2. Attacker 
    
   Attacker is individual who attempts one or more attacks in order to 
   achieve an objective(s).  
    
   For the purpose of IODEF attacker is described by its network ID, 
   organisation which network/computer attack was originated and 
   physical location information (optional). 
    
   3.2.3. CSIRT 
    
   CSIRT is used in IODEF to refer to the authority handling the 
   Incident and creating Incident Object Description. The CSIRT is also 
   likely to be involved in evidence collection and custody, incident 
   remedy, etc. 
    
   In IODEF CSIRT represented by its ID, constituency, public key, etc. 
    
   3.2.4. Damage 
    
   An intended or unintended consequence of an attack which affects the 
   normal operation of the targeted system or service. Description of 
   damage may include free text description of actual result of attack, 
   and, where possible, structured information about the particular 
   damaged system, subsystem or service.  
 

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   3.2.5. Event 
    
   An action directed at a target which is intended to result in a 
   change of state (status) of the target. From the point of view of 
   event origination, it can be defined as any observable occurrence in 
   a system or network which resulted in an alert being generated. For 
   example, three failed logins in 10 seconds might indicate a brute-
   force login attack. 
    
   3.2.6. Evidence  
    
   Evidence is information relating to an intrusion that proves (or 
   supports) a conclusion about fact of attack.  
   It may include but is not limited to: data dump created by Intrusion 
   Detection System (IDS), data from syslog file, kernel statistics, 
   cache, memory, temporary file system, or other data that caused the 
   alert or were collected after the incident happened.  
    
   Special rules and care must be taken when storing and archiving 
   evidence, particularly to preserve its integrity. When necessary 
   evidence should be stored encrypted.  
   According to Guidelines for Evidence Collection and Archiving 
   (Evidence) evidence must be strictly secured. The chain of evidence 
   custody needs to be clearly documented. 
    
   3.2.7. Incident 
    
   Incident is a security event that involves a security violation. An 
   incident can be defined as a group of attacks that can be 
   distinguished from other attacks by the method of attack, identity 
   of attackers, victims, sites, objectives or timing. 
    
   In context of IODEF term Incident is used in meaning of Computer 
   Security Incident or IT Security Incident.  
    
   Incident is a root/key element of the discussed IODEF. Incident 
   object data model is described by separate document.  
    
   3.2.8. Impact  
    
   Impact describes result of attack expressed in terms of user 
   community, for example the cost in terms of financial or other 
   disruption   
    
   3.2.9. Target 
    
   A computer or network logical entity (account, process or data) or 
   physical entity (component, computer, network or internetwork). 
    
   3.2.10. Victim 
    
   Victim is individual or organisation which suffered the attack  
   which is described in incident report. 
 

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   For the purpose of IODEF victim is described by its network ID, 
   organisation and location information. 
    
   3.2.11. Vulnerability 
    
   A flaw or weakness in a system's design, implementation, or 
   operation and management that could be exploited to violate the 
   system's security policy. 
    
   Most systems have vulnerabilities of some sort, but this does not 
   mean that the systems are too flawed to use. Not every threat 
   results in an attack, and not every attack succeeds. Success depends 
   on the degree of vulnerability, the strength of attacks, and the 
   effectiveness of any countermeasures in use. If the attacks needed 
   to exploit a vulnerability are very difficult to carry out, then the 
   vulnerability may be tolerable. If the perceived benefit to an 
   attacker is small, then even an easily exploited vulnerability may 
   be tolerable. However, if the attacks are well understood and easily 
   made, and if the vulnerable system is employed by a wide range of 
   users, then it is likely that there will be enough benefit for 
   someone to make an attack. 
    
   3.2.12. Other terms 
    
   Other terms used: alert, activity, IDS, Security Policy, etc. - are 
   defined in related I-Ds, RFCs and standards [3, 6, 7, 8, 9, 10].  
    
    
4. General Requirements  
    
   4.1. The IODEF shall reference and use previously published RFCs 
   where possible. 
    
   Comment:  
   The IETF has already developed a number of standards in the areas of 
   networks and security that are actually deployed in present 
   Internet. Current standards provide framework for compatibility of 
   IODEF with other related technologies necessary to operate 
   /implement IODEF in practice. Another issue of compatibility for the 
   IODEF is its general compatibility with IDEF currently being 
   developed by IETF IDEWG. In the interest of time and compatibility, 
   defined and accepted standards should be used wherever possible. 
    
   In particularly, IODEF specification proposals SHOULD rely heavily 
   on existing communications, encryption and language standards, where 
   possible. 
    
5. Description Format 
    
   5.1. IODEF shall support full internationalization and localization. 
    
   Comment:  

 
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   Since some Incidents need involvement of CSIRTs from different 
   countries, cultural and geographic regions, the IODEF description 
   must be formatted such that they can be presented to an operator in 
   a local language and adhering to local presentation formats. 
    
   Although metalanguage for IODEF identifiers and labels is considered 
   to be English, a local IODEF implementation might be capable to 
   translate metalanguage identifiers and labels into local language 
   and presentations if necessary.  
    
   Localized presentation of dates, time and names may also be 
   required. In cases where the messages contain text strings and names 
   that need characters other than Latin-1 (or ISO 8859-1), the 
   information preferably should be represented using the ISO/IEC IS 
   10646-1 character set and encoded using the UTF-8 transformation 
   format, and optionally using local character sets and encodings [9]. 
    
    
   5.2. The IODEF must support modularity in Incident description to 
   allow aggregation and filtering of data. 
    
   Comment: 
   It is suggested that Incident description with IODEF might include 
   external information, e.g. from IDS, or reference externally stored 
   evidence custody data, or such information might be removed from 
   current IODEF description, e.g. in purposes of privacy or security. 
   Another practical/real life motivation for this requirement is to 
   give possibility for some CSIRTs/managers to perform filtering 
   and/or data aggregation functions on IODEF descriptions for the 
   purposes of statistics, reporting and high level Incident 
   information exchange between CSIRTs and/or their constituency and 
   sponsors.  
    
   Therefore the IODEF descriptions MUST be structured to facilitate 
   these operations. This also implies to strong IODEF semantics. 
    
   5.3. IODEF must support the application of an access restriction 
   policy attribute to every element. 
    
   Comment: 
   IODEF Incident descriptions potentially contain sensitive or private 
   information (such as passwords, persons/organisations identifiers or 
   forensic information (evidence data)) and in some cases may be 
   exposed to non-authorised persons. Such situations may arise 
   particularly in case of Incident information exchange between CSIRTs 
   or other involved bodies. Some cases may be addressed by encrypting 
   IODEF elements, however this will not always be possible.  
    
   Therefore, to prevent accidental disclosure of sensitive data, parts 
   of the IODEF object must be marked with access restriction 
   attributes. These markings will be particularly useful when used 
   with automated processing systems. 
    
    
 
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6. Communications Mechanisms Requirements 
    
   6.1. IODEF exchange will normally be initiated by humans using 
   standard communication protocols, for example, e-mail, WWW/HTTP, 
   LDAP. 
    
   Comment: 
   IODEF description is normally created by a human using special or 
   standard text editors. The IODEF is targeted to be processed by 
   automated Incident handling systems but still must be human 
   readable, able to be viewed and browsed with standard tools (e.g. 
   browsers or electronic table processors or database tools like MS 
   Excel or Access). Incident information exchange will normally 
   require authorisation by  an operator or CSIRT manager so is not 
   expected to be initiated automatically. The role of Incident 
   handling system is to provide assistance and tools for performing 
   the exchange. 
    
   It is important to distinguish the purposes of the machine readable 
   and exchangeable IDEF Intrusion message format and the human 
   oriented and created IODEF Incident description.  
    
   Communications security requirements will be applied separately 
   according to local policy so are not defined by this document. 
    
7. Message Contents 
    
   7.1. The root element of the IO description should contain a unique 
   identification number (or identifier), IO purpose and default 
   permission level 
    
   Comment: 
   Unique identification number (or identifier) is necessary to 
   distinguish one Incident from another. It is suggested that unique 
   identification number will contain information at least about IO 
   creator, i.e. CSIRT or related body. The classification of the 
   Incident may also be used to form a unique identification number. IO 
   purpose will actually control which elements are included in the 
   IODEF object Purposes may include incident alert/registration, 
   handling, archiving, reporting or statistics. The purpose, incident 
   type or status of Incident investigation may require different 
   levels of access permission for the Incident information. 
    
   It is considered that root element of the IODEF will be <INCIDENT> 
   and additional information will be treated as attributes of the root 
   element. 
    
   7.2. The content of the IODEF description should contain the type of 
   the attack if it is known.  
   It is expected that this type will be drawn from a standardized list 
   of events; a new type of event may use a temporary implementation-
   specific type if the event type has not yet been standardized. 
    
   Comment: 
 

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   Incident handling may involve many different staff members and 
   teams. It is therefore essential that common terms are used to 
   describe incidents.   
   If the event type has not yet been standardized, temporary type 
   definition might be given by team created IO. It is expected that 
   new type name will be self-explanatory and derived from a similar, 
   existing type definition.  
    
    
   7.3. The IODEF description must be structured such that any relevant 
   advisories, such as those from CERT/CC, CVE, can be referenced. 
    
   Comment: 
   Using standard Advisories and lists of known Attacks and 
   Vulnerabilities will allow the use of their recommendations on 
   Incident handling/prevention. Such information might be included as 
   an attribute to the attack or vulnerability type definition. 
    
   7.4. IODEF may include a detailed description of the attack that 
   caused the current Incident.  
    
   Comment: 
   Description of attack includes information about attacker and 
   victim, the appearance of the attack and possible impact. At the 
   early stage of Intrusion alert and Incident handling there is likely 
   to be minimal information, during handling of the Incident this will 
   grow to be sufficient for Incident investigation and remedy.  
   Element <ATTACK> should be one of the main elements of Incident 
   description. 
    
   7.5. The IODEF description must include or be able to reference 
   additional detailed data related to this specific underlying 
   event(s)/activity, often referred as evidence.  
    
   Comment: 
   For many purposes Incident description does not need many details on 
   specific event(s)/activity that caused the Incident; this 
   information may be referenced as external information (by means of 
   URL). In some cases it might be convenient to store separately 
   evidence that has different access permissions. It is foreseen that 
   another standard will be proposed for evidence custody [5]. 
    
   7.6. The IODEF description MUST contain the description of the 
   attacker and victim.  
    
   Comment: 
   This information is necessary to identify the source and target of 
   the attack. The minimum information about attacker and victim is 
   their IP or Internet addresses, extended information will identify 
   their organisations allowing CSIRTs to take appropriate measures for 
   their particular constituency.  
  
 
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   7.7. The IODEF description must support the representation of 
   different types of device addresses, e.g., IP address (version 4 or 
   6) and Internet name. 
    
   Comment: 
   The sites from which attack is launched might have addresses in 
   various levels of the network protocol hierarchy (e.g., Data layer 2 
   MAC addresses or Network layer 3 IP addresses). Additionally, the 
   devices involved in an intrusion event might use addresses that are 
   not IP-centric, e.g. ATM-addresses. It is also understood that 
   information about the source and target of the attack might be 
   obtained from IDS and include the IP address, MAC address or both.  
    
   7.8. IODEF must include the Identity of the creator of the Incident 
   Object (CSIRT or other authority). This may be the sender in an 
   information exchange or the team currently handling the incident. 
    
   Comment: 
   The identity of Incident description creator is often valuable 
   information for Incident response. In one possible scenario the 
   attack may progress through the network, comparison of corresponding 
   incidents reported by different authorities might provide some 
   additional information about the origin of the attack. This is also 
   useful information at post-incident information handling/exchange 
   stage.  
    
   7.9. The IODEF description must contain an indication of the 
   possible impact of this event on the target. The value of this field 
   should be drawn from a standardized list of values if the attack is 
   recognized as known, or expressed in a free language by responsible 
   CSIRT team member.  
    
   Comment: 
   Information concerning the possible impact of the event on the 
   target system provides an indication of what the attacker is 
   attempting to do and is critical data for the CSIRTs to take actions 
   and perform damage assessment. If no reference information 
   (Advisories) is available, this field may be filled in based on 
   CSIRT team experience. 
    
   It is expected that most CSIRTs will develop Incident handling 
   support systems, based on existing Advisories (such as those from 
   CERT/CC, CVE, etc.) that usually contain list of possible impacts 
   for identified attacks.  
    
   This also relates to the development of IDEF which will be 
   implemented in intelligent IDS,  able to retrieve information from 
   standard databases of attacks and vulnerabilities [3].  
    
   7.10. The IODEF must be able to state the degree of confidence in 
   the report information.  
    
   Comment: 


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   Including this information is essential at the stage of Incident 
   creation, particularly in cases when intelligent automatic IDS or 
   expert systems are used. These normally use statistical engines to 
   estimate the event probability. 
    
   7.11. The IODEF description must provide information about the 
   actions taken in the course of this incident by previous CSIRTs. 
    
   Comment: 
   The IODEF describes an Incident throughout its life-time from Alert 
   to closing and archiving. It is essential to track all actions taken 
   by all involved parties. This will help determine what further 
   action needs to be taken, if any. This is especially important in 
   case of Incident information exchange between CSIRTs in process of 
   investigation. 
    
   7.12. The IODEF must support reporting of the time of all stages 
   along Incident life-time. 
    
   Comment: 
   Time is important from both a reporting and correlation point of 
   view. Time is one of main components that can identify the same 
   Incident or attack if launched from many sites or distributed over 
   the network. Time is also essential to be able to track the life of 
   an Incident  including Incident exchange between CSIRTs in process 
   of investigating.  
    
   7.13. Time shall be reported as the local time and time zone offset 
   from UTC.  
   (Note: See RFC 1902 for guidelines on reporting time.) 
    
   Comment: 
   For event correlation purposes, it is important that the manager be 
   able to normalize the time information reported in the IODEF 
   descriptions. 
    
   7.14. The format for reporting the date must be compliant with all 
   current standards for Year 2000 rollover, and it must have 
   sufficient capability to continue reporting date values past the 
   year 2038. 
    
   Comment: 
   It is stated in the purposes of the IODEF that the IODEF shall 
   describe the Incident throughout its life-time. In the case of 
   archiving this duration might be unlimited. Therefore, 
   implementations that limit expression of time value (such as 2038 
   date representation limitation in "Unix time") MUST be avoided. 
    
   7.15. Time granularity in IO time parameters shall not be specified 
   by the IODEF. 
    
   Comment: 
   The time data may be included into IODEF description by existing 
   information systems, retrieved from incident reporting messages or 

 
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   taken from IDS data or other event registration tools. Each of these 
   cases may have its own different time granularity. For the purposes 
   of implementation, it should be possible to handle time at different 
   stages according to the local system capabilities.  
    
   7.16. The IODEF should support confidentiality of the description 
   content.  
   The selected design should be capable of supporting a variety of 
   encryption algorithms and must be adaptable to a wide variety of 
   environments. 
    
   Comment: 
   IODEF Incident descriptions potentially contain sensitive or private 
   information (such as forensic data (evidence data), passwords, or 
   persons/organisations identifiers) which would be of great interest 
   to an attacker or malefactor. Incident information normally will be 
   stored on a networked computer, which potentially may be exposed to 
   attacks (or compromised). Incident information may be transmitted 
   across uncontrolled network segments. Therefore, it is important 
   that the content be protected from unauthorised access and 
   modification. Furthermore, since the legal environment for privacy 
   and encryption technologies are varied from regions and countries 
   and change often, it is important that the design selected be 
   capable of supporting a number of different encryption options and 
   be adaptable by the user to a variety of environments. 
   Additional measures may be undertaken for securing the Incident 
   during communication but this issue is outside of IODEF scope as it 
   implies more strict rules for IO archiving and storing in general. 
    
   7.17. The IODEF should ensure the integrity of the description 
   content.  
   The selected design should be capable of supporting a variety of 
   integrity mechanisms and must be adaptable to a wide variety of 
   environments. 
    
   Comment: 
   Special measures should be undertaken to prevent malicious IO 
   changes. 
   Additional measures may be undertaken for securing the Incident 
   during communication but this issue is outside of IODEF scope.  
    
   7.18. The IODEF should ensure the authenticity and non-repudiation 
   of the message content.  
    
   Comment:  
   Authenticity and accountability is needed by many teams, especially 
   given the desire to automatically handle IOs, therefore it MUST be 
   included in the IODEF. Because of the importance of IO authenticity 
   and non-repudiation to many teams and especially in case of 
   communication between them, the implementation of these requirements 
   is strongly RECOMMENDED. 
    
   7.19. The IODEF description must support an extension mechanism 
   which may be used by implementers. This allows future 
 

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   implementation-specific or experimental data. The implementer MUST 
   indicate how to interpret any included extensions. 
   Comment: 
   Implementers might wish to supply extra data such as information for 
   internal purposes or necessary for the particular implementation of 
   their Incident handling system. These data may be removed or not in 
   external communications but it is essential to mark them as 
   additional to prevent wrong interpretation by different systems. 
    
   7.20. The semantics of the IODEF description must be well defined. 
    
   Comment: 
   IODEF is a human oriented format for Incident description, and IODEF 
   description should be capable of being read by humans. The use of 
   automatic parsing tools is foreseen but should not be critically 
   necessary. Therefore, IODEF must provide  good semantics, which will 
   be  key to understanding what the description contains. In some 
   cases the IODEF description will be used for  automatic decision 
   making, so it is important that the description be interpreted 
   correctly. This is an argument for using language-based semantics . 
   The metalanguage for IODEF identifiers and labels is proposed to be 
   English, a local IODEF implementation might be able to translate 
   metalanguage identifiers and labels into local language and 
   presentations if necessary.  
    
8. IODEF extensibility  
    
   8.1. The IODEF itself MUST be extensible. It is essential that when 
   the use of new technologies and development of automated Incident 
   handling system demands extension of IODEF, the IODEF will be 
   capable to include new information.  
    
    
   Comment: 
   In addition to the need to extend IODEF to support new Incident 
   handling tools, it is also suggested that IODEF will incorporate new 
   developments from related standardisation areas such as IDEF for IDS 
   or the development of special format for evidence custody. The 
   procedure for extension should be based on CSIRT/IODEF community 
   acceptance/approval. 
    
9. Security considerations 
    
   This memo describes requirements to an Incident Object Description 
   and Exchange Format, which intends to define a common data format 
   for the description, archiving and exchange of information about 
   incidents between CSIRTs (including alert, incident in 
   investigation, archiving, statistics, reporting, etc.). In that 
   respect the implementation of the IODEF is a subject to security 
   considerations. Particular security requirement to access 
   restriction indication is discussed in section 5.3, requirements to 
   Incident description confidentiality, integrity, authenticity and 
   non-repudiation are described in sections 7.16, 7.17, 7.18. 
    
 

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10. Reference 
    
   [1]  Bradner, S., "Key words for use in RFCs to Indicate Requirement 
        Levels", BCP 14, RFC 2119, March 1997 
    
   [2]  Incident Taxonomy and Description Working Group Charter -  
        http://www.terena.nl/task-forces/tf-csirt/i-taxonomy/ 
    
   [3]  Intrusion Detection Exchange Format Requirements by Wood, M. -  
        October 1999. - http://www.ietf.org/internet-drafts/draft-ietf- 
        idwg-requirements-02.txt 
    
   [4]  Intrusion Detection Message Exchange Format Extensible Markup  
        Language (XML) Document Type Definition by D. Curry - March  
        2000 - http://www.ietf.org/internet-drafts/draft-ietf-idwg- 
        idmef-xml-01.txt 
    
   [5]  Guidelines for Evidence Collection and Archiving by Dominique  
        Brezinski, Tom Killalea - July 2000. -  
        http://www.ietf.org/internet-drafts/draft-ietf-grip-prot- 
        evidence-01.txt 
    
   [6]  RFC2350. Best Current Practice;  Expectations for Computer  
        Security Incident Response by N. Brownlee, E. Guttman. - June 
        1998. - http://www.ietf.org/rfc/rfc2350.txt 
    
   [7]  RFC 2828. Internet Security Glossary by R. Shirey. May 2000. - 
        http://www.ietf.org/rfc/rfc2828.txt 
    
   [8]  Establishing a Computer Security Incident Response Capability  
        (CSIRC). NIST Special Publication 800-3, November, 1991 
    
   [9]  Handbook for Computer Security Incident Response Teams  
        (CSIRTs), Moira J. West-Brown, Don Stikvoort, Klaus-Peter  
        Kossakowski. - CMU/SEI-98-HB-001. - Pittsburgh, PA: Carnegie 
        Mellon University, 1998. 
    
   [10] A Common Language for Computer Security Incidents by John D. 
        Howard and Thomas A. Longstaff. -  Sandia Report: SAND98-8667, 
        Sandia National Laboratories -  
        http://www.cert.org/research/taxonomy_988667.pdf 
    
   [11] Best Current Practice of incident classification and reporting 
        schemes currently used by active CSIRTs. -  
        http://www.terena.nl/task-forces/tf-csirt/i- 
        taxonomy/docs/BCPreport1.rtf 
    
   [12] Multilingual Support in Internet/IT Applications. -  
        http://www.terena.nl/projects/multiling/ 
    
    
Acknowledgements: 
    
 
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   This document was discussed at the Incident Taxonomy and Description 
   Working Group seminars (http://www.terena.nl/task-forces/tf-
   csirt/tf-csirt000929prg.html#itdwg) in the frame of TERENA Task 
   Force TF-CSIRT (http://www.terena.nl/task-forces/tf-csirt/).  
   Incident Taxonomy and Description Working Group at TERENA can be 
   contacted via the mailing lists <incident-taxonomy@terena.nl> or 
   <iodef@terena.nl>, archives are available correspondently at 
   http://hypermail.terena.nl/incident-taxonomy-list/mail-archive/ and 
   http://hypermail.terena.nl/iodef-list/mail-archive/ 
    
   Authors Address: 
    
   Jimmy Arvidsson  
   Jimmy.J.Arvidsson@telia.se 
   Telia CERT 
    
   Andrew Cormack  
   Andrew.Cormack@ukerna.ac.uk 
   JANET-CERT 
    
   Yuri Demchenko  
   demch@terena.nl 
   TERENA 
    
   Jan Meijer  
   jan.meijer@surfnet.nl 
   SURFnet 
    
    
Full Copyright Statement 
    
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   "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 
 

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   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF 
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 




















































    
 
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