Internet Engineering Task Force                           ShinNetwork Working Group                                        S. Miyakawa
Internet-Draft                            NTT Communications
<draft-ietf-ipv6-prefix-delegation-requirement-00.txt> Corporation
Expires: May 1, Aug 25, 2003					     R. Droms
                                                           Cisco Systems
                                                                Feb 2003
                                                          Nov 1, 2002

                Requirements for IPv6 prefix delegation

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-

   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 "work in progress.''

To view the progress."

   The list of current Internet-Drafts can be accessed at

   The list of Internet-Draft Shadow Directories, see Directories can be accessed at

Distribution of this memo is unlimited.

The internet-draft

   This Internet-Draft will expire in 6 months.  The date of expiration will
be May 1, on Aug 25, 2003.

Copyright Notice

   Copyright (C) The Internet Society (2003).  All Rights Reserved.


   This document describes requirements about for how an IPv6 address prefix prefixes
   should be delegated to an IPv6 subscriber's network (or "site").


1. Introduction

   With the deployment of IPv6 [Deering, 1998] ,several commercial ISPs [2], several Internet Service Providers
   are ready to offer their services IPv6 access to the public in public.  In conjunction with
   widely deployed IP subscription method such "always on" media as ADSL ADSL, and so on.  But,
   thinking about following situation of IPv6 commercial service as one
   of the most likely examples,

           IPv6 ISP router
             | point-to-point link
           User's Site router
         ----+----- User's Site Network

   though it is needed expectation that
   customers will be assigned a standardized way to delegate one or more /48 IPv6 address prefix(es) from the IPv6 ISP prefix, an efficient
   mechanism for delegating address prefixes to the User's site
   automatically, it customers sites is not identified clearly yet.

   Originally, it seemed that just RA (Router Avertisement) considered
   as good enough to
   needed.  The delegation mechanism will be used for P-P link between ISP and User's site,
   but according intended to automate the NCCs' recommendations, one site should be
   delegated /48 usually.

   So, ISP which now would like to start its own IPv6 commercial service
   TODAY, need to have some method other than RA protocol which only can
   handle one signle /64 prefix but something else or enhanced

   - to delegate not just one signle /64 prefix to
   process of informing the user - to satisfy
   all customer's networking equipment of the other (standard) requirements which is needed
   prefixes to realize
   commercial service

   Therefore, this documents be used at the customer's site.

   This document clarifies the requirements for IPv6 address prefix
   delegation from the ISP to the site, especially from the
   (commercial) ISP point of view site.

2. Requirements

   SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL in this document are to boost IPv6 business quick be
   interpreted as

   Requirements described in RFC2119 [1].

3. Scenario and terminology

   The following figure illustrates a likely example for prefix delegation management
   Focusing commercial IPv6 ISP service, there are several kinds the
   organization of
   category a network providing subscription IPv6 service:

                                                    /        \
                                                   +          |
                                                  / \        /
        +---------------+              +--------+/   \------/
        |ISP Edge Router|Point-to-point|Customer+
        |               +--------------+ Router |  Customer networks
        |     (PE)      |     link     | (CPE)  +
        +---------------+              +--------+\   /------\
                                                  \ /        \
                                                   +          |
                                                    \        /

   Illustration of requirements ISP-customer network architecture


   PE Provider edge device; the device at which the link to the customer
      site is terminated

   CPE Customer provided equipment; the device at the customer site at
      which the link to the ISP is terminated

4. Requirements for Prefix Delegation

   The purpose of the prefix delegation mechanism / protocol is to delegate one
   or more IPv6 communicate
   prefixes from ISP to a site.

   - layer 2 consideration

   The method should the CPE automatically.

4.1 Number and Length of Delegated Prefixed

   The prefix delegation mechanism SHOULD allow for delegation of
   prefixes of length /48, /64 and other lengths, and SHOULD allow for
   delegation of more than one prefix to the customer.

4.2 Use of Delegated Prefixes in Customer Network

   The prefix delegation mechanism MUST NOT prohibit or inhibit the
   assignment of longer prefixes, created from the delegated prefixes,
   to links within the customer network.  It is not a requirement that
   the prefix delegation mechanism provide for the reporting of prefix
   delegation within the customer network back to the ISP.

4.3 Automated Assignment

   The prefix delegation mechanism SHOULD allow for long-lived pre-
   assignment of one or more prefix(es) to a customer and for
   automated, possibly short-lived assignment of a prefix to a customer
   on demand.

4.4 Policy-based Assignment

   The prefix delegation mechanism SHOULD allow for the use of policy in
   assigning prefixes to a customer.  For example, the customer's
   identity and type of subscribed service may be used to determine the
   address block from which the customer's prefix is selected, and the
   length of the prefix assigned to the customer.

4.5 Security and Authentication

   The prefix delegation mechanism MUST provide for reliable
   authentication of the identity of the customer to which the prefixes
   are to be assigned, and MUST provide for reliable, secure
   transmission of the delegated prefixes to the customer.

4.6 Accounting

   The prefix delegation mechanism MUST allow for the ISP to provide
   accounting information about delegated prefixes.

4.7 Layer 2 Considerations

   The method SHOULD work on any layer 2 technologies.  In other words,
   it should be layer 2 technology independent.  Though, at the same
   time, it should be noted that now ISP would like to have a solution
   for Point-to-Point link which has own authentication mechanism first.
   PPP link with CHAP authentication is a good example.  (Simulated)
   Ethernet and IEEE802.11 (wireless LAN) should be covered in near
   future, but they have low priority (just) for now.  It should be
   clarified that the method should work with all L2 protocols either
   with authentication mechanism or without, but ISP would like to take
   advantage of a L2 protocol's authentication mechanism if it exits.

   - accounting

   It should provide accounting capability such as logging about by
   whom, when and what prefix(es) is used

5. IANA Considerations

   There are no IANA considerations in this document.

6. Security considerations

   Section 4.5 specifies security requirements for the service with proper
   authentication techniques.

   - kinds of prefixes

   It should be able prefix delegation


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

   [2]  Deering, S. and dynamically
   assigned prefix assignment by authenticated identification, depended
   by resources and/or any reasons.

   - negotiation between ISP R. Hinden, "Internet Protocol, Version 6 (IPv6)
        Specification", RFC 2460, December 1998.

Author's Address

   Shin Miyakawa
   Innovative IP Architecture Center, NTT Communications Corporation
   Tokyo Opera City Tower 21F, 3-20-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo,
   Phone: +81-3-6800-3262

   Ralph Droms
   Cisco Systems
   300 Apollo Drive
   Chelmsford, MA 01886
   Phone: +1-978-497-4733

Full Copyright Statement

   Copyright (C) The Internet Society (2003).  All Rights Reserved.

   This document and site

   ISP translations of it may deny the service, due be copied and furnished to various reasons such as there is no
   others, and derivative works that comment on or bad financial credit etc.  Also ISP should otherwise explain it
   or assist in its implementation may be able to use
   one single technique to pass parameters prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the prefix above copyright notice and this paragraph are
   included on all such as scope
   (global and/or site), prefix length (/48, /64 or any other length) copies and any other appropriate related information to the site.  On the
   other hand, a site should derivative works.  However, this
   document itself may not be able to request multiple prefixes to modified in any way, such as by removing
   ISP.  Also a site should be able copyright notice or references to pass parameters of the prefix
   such as scope (global and/or site), prefix length (/48, /64 Internet Society or any other length), number of prefixes and so on to
   Internet organizations, except as needed for the ISP to negotiate.

   - less impact on ISP equipments

   ISP usualy use some kind purpose of equipment to provide subscription service
   developing Internet standards in which case the users such as access concentrating router, PPP server and so
   on.  This may aggregate thousands or more connections toward procedures for
   copyrights defined in the
   ISP's backbone.  Prefix delegation mechanism Internet Standards process must be compatible with
   this situation.

   References Deering, 1998.  S. Deering and R. Hinden, "Internet
   Protocol, Version 6 (IPv6) Specification", RFC2460 (December 1998).

   Jun 2002, first draft was presented
   followed, or as personal submission.
   At the IETF-54th at Yokohama, required to translate it became a working group draft.
   Nov 2003, the draft published as -01 draft.

   People in Internet Association of Japan have gave me a lot of good input.
   Team members of NTT Communications IPv6 project, especially Toshi Yamasaki
   and Yasuhiro Shirasaki, gave me quite useful suggestions for this
   document. Chairs of IETF IPv6 working group especially Bob Hinden
   who gave me a good suggestions before I submitted this draft.
   Also communications with into languages other folks in the IPv6 community, such
   as WIDE/KAME project, IPv6 than

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

   This document and so the information contained herein is provided on have
   been quite helpful. Thanks a lot.

Author's address
   Shin Miyakawa, Ph.D
   Innovative IP Architecture Center, NTT Communications Corporation
   Tokyo, Japan
   Tel: +81-3-6800-3262
   Fax: +81-3-5265-2990
   Email: an


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