WDIFF

draft-ietf-ipv6-unicast-aggr-v2-03.txt-7779.txt --> rfc3587.txt

INTERNET-DRAFT

Network Working Group R. Hinden, Hinden
Request for Comments: 3587 Nokia
June 19, 2003
Obsoletes: 2374 S. Deering, Deering
Category: Informational Cisco
E. Nordmark, Nordmark
Sun
August 2003

IPv6 Global Unicast Address Format

<draft-ietf-ipv6-unicast-aggr-v2-03.txt>

Status of this Memo

This document is an Internet-Draft and is subject to all provisions
of Section 10 of RFC2026.

Internet-Drafts are working documents of memo provides information for the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum community. It does
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The list kind. Distribution of current Internet-Drafts can be accessed at
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memo is unlimited.

Abstract

RFC2374

This document obsoletes RFC 2374, "An IPv6 Aggregatable Global
Unicast Address Format" Format". It defined an IPv6 address allocation
structure that includes TLA (Top Top Level
Aggregator) Aggregator (TLA) and NLA (Next Next Level Aggregator).
Aggregator (NLA). This document replaces
RFC2374, and makes RFC 2374 and the TLA/NLA
structure historic.

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1.0

1. Introduction

RFC2374

RFC 2374, "An IPv6 Aggregatable Global Unicast Address Format" Format",
defined an IPv6 address allocation structure that includes TLA (Top Level
Aggregator) and NLA (Next Level Aggregator).
NLA. This document replaces
RFC2374, RFC 2374, and makes RFC 2374 and the
TLA/NLA structure historic.

2.0

2. TLA/NLA Made Historic

The TLA/NLA scheme has been replaced by a coordinated allocation
policy defined by the Regional Internet Registries (RIRs) [IPV6RIR].

Part of the motivation for obsoleting the TLA/NLA structure is
technical; for instance, there is concern that TLA/NLA is not the
technically best approach at this stage of the deployment of IPv6.
Moreover, the allocation of IPv6 addresses is related to policy and
to the stewardship of the IP address space and routing table size,
which the RIRs have been managing for IPv4. It is likely that the
RIRs' policy will evolve as IPv6 deployment proceeds.

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RFC 3587 IPv6 Global Unicast Address Format August 2003

The IETF has provided technical input to the RIRs (for example,
[RFC3177]), which the RIRs have taken into account when defining
their address allocation policy.

RFC2374

RFC 2374 was the definition of addresses for Format Prefix 001
(2000::/3) which is formally made historic by this document. Even
though currently only 2000::/3 is being delegated by the IANA,
implementations should not make any assumptions about 2000::/3 being
special, since
special. In the future, the IANA might later be directed to delegate
currently unassigned parts portions of the IPv6 address space to for the
purpose of Global Unicast as well.

The SLA (subnet local aggregator) Subnet Local Aggregator (SLA) field in RFC2374 RFC 2374 remains in
function but with a different name in [ARCH]. Its new name is
"subnet ID".

This documented replaces RFC2374, "An IPv6 Aggregatable Global
Unicast Address Format". RFC2374 will become historic.

3.0

3. Address Format

The general format for IPv6 global unicast addresses as defined in
"IP Version 6 Addressing Architecture" [ARCH] is as follows:

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where the global routing prefix is a (typically hierarchically-
structured)
hierarchically-structured) value assigned to a site (a cluster of
subnets/links), the subnet ID is an identifier of a subnet within the
site, and the interface ID is as defined in section 2.5.1 of [ARCH].
The global routing prefix is designed to be hierarchically structured hierarchically
by the RIRs and ISPs, and the ISPs. The subnet field is designed to be hierarchically structured
hierarchically by site administrators.

[ARCH] also requires that all unicast addresses, except those that
start with binary value 000, have Interface IDs that are 64 bits long
and to be constructed in Modified EUI-64 format. The format of
global unicast address in this case is:

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where the routing prefix is a value assigned to identify a site (a
cluster of subnets/links), the subnet ID is an identifier of a subnet
within the site, and the interface ID is in a modified EUI-64 format as
defined in [ARCH].

An example of the resulting format of global unicast address under
the 2000::/3 prefix that is currently being delegated by the IANA and
consistent with the recommendations in RFC3177 RFC 3177 is:

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4.0

4. Acknowledgments

The authors would like to express our thanks to Alain Durand, Brian
Carpenter, Fred Templin, Julian Sellers, Jun-ichiro itojun Itojun Hagino,
Margaret Wasserman, Michel Py, Pekka Savola, Tatuya Jinmei, and
Thomas Narten for their review and constructive comments.

5.0

5. References

5.1. Normative References

[ARCH] Hinden, R., R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC3513, RFC 3513, April 2003.

[IPV6] Deering, S., S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC2460, RFC 2460, December 1998.

Non-Normative

5.2. Informative References

[IPV6RIR] APNIC, ARIN, RIPE NCC, "IPv6 Address Allocation and
Assignment Policy", Document ID: ripe-267,
http://www.ripe.net/ripe/docs/ipv6policy.html, January 22,
2003.

[RFC3177] IAB/IESG, "Recommendations on IPv6 Address Allocations to
Sites" RFC3177,
Sites", RFC 3177, September 2001.

6.0

6. Security Considerations

IPv6 addressing documents do not have any direct impact on Internet
infrastructure security.

7.0

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7. Authors' Addresses

Robert M. Hinden email: bob.hinden@nokia.com
Nokia
313 Fairchild Drive
Mountain View, CA
US
USA

EMail: bob.hinden@nokia.com

Stephen E. Deering email: deering@cisco.com
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
US

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USA

Erik Nordmark email: erik.nordmark@sun.com
Sun Microsystems Laboratories
180, avenue de l'Europe
38334 SAINT ISMIER Cedex
France

draft-ietf-ipv6-unicast-aggr-v2-03.txt

EMail: erik.nordmark@sun.com

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8. 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
or assist in its implementation may be prepared, copied, published
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The limited permissions granted above are perpetual and will not be
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This document and the information contained herein is provided on an
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HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

Funding for the RFC Editor function is currently provided by the
Internet Society.

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