IPv6 CE Routers LAN Prefix Delegation
draft-winters-v6ops-cpe-lan-pd-01

Internet Engineering Task Force                               T. Winters
Internet-Draft                                                   QA Cafe
Updates: 7084 (if approved)                                10 March 2023
Intended status: Informational                                          
Expires: 11 September 2023

                 IPv6 CE Routers LAN Prefix Delegation
                   draft-winters-v6ops-cpe-lan-pd-01

Abstract

   This document defines requirements for IPv6 CE Routers to support
   DHCPv6 Prefix Delegation for redistributing any unused prefix(es)
   that were delegated to the IPv6 CE Router.  This document updates RFC
   7084.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   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."

   This Internet-Draft will expire on 11 September 2023.

Copyright Notice

   Copyright (c) 2023 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Winters                 Expires 11 September 2023               [Page 1]
Internet-Draft    IPv6 CE Routers LAN Prefix Delegation       March 2023

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   2
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Architecture  . . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  Requirements  . . . . . . . . . . . . . . . . . . . . . . . .   3
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
   8.  Acknowledements . . . . . . . . . . . . . . . . . . . . . . .   4
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   4
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   5
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   5
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   5

1.  Introduction

   This document defines DHCPv6 Prefix Delegation in IPv6 CE Routers
   ([RFC7084]) in order to properly utilize the IPv6 prefixes assigned
   by service providers.  Many ISP will assign a prefix larger then /64
   to the CE Router as recommended in [RFC6177].  If a IPv6 CE Router
   doesn't support IA_PD on the LAN it will not be able to assign any
   prefixes beyond itself limiting the usefulness of assigning prefixes
   larger then /64.  Supporting IA_PD on the LAN interfaces will allow
   for those prefixes to be distributed into a network to be useable.
   This document does not cover dealing with multi provisioned networks
   with more then one provider.

2.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   This document also makes use of internal conceptual variables to
   describe protocol behavior and external variables that an
   implementation must allow system administrators to change.  The
   specific variable names, how their values change, and how their
   settings influence protocol behavior are provided to demonstrate
   protocol behavior.  An implementation is not required to have them in
   the exact form described here, as long as its external behavior is
   consistent with that described in this document.

Winters                 Expires 11 September 2023               [Page 2]
Internet-Draft    IPv6 CE Routers LAN Prefix Delegation       March 2023

3.  Terminology

   The following terminology is defined for this document.

   *  IPv6 CE Router: A router intended for home or small-office use
      that forwards packets not explicitly addressed to itself as
      defined in [RFC7084].

   *  Internet Service Provider (ISP): An entity that provides access to
      the Internet.  In this document, a service provider specifically
      offers Internet access using IPv6, and may also offer IPv4
      Internet access.  The service provider can provide such access
      over a variety of different transport methods such as DSL, cable,
      wireless, and others.

4.  Architecture

                        +-----------+
                        |  Service  |
                        |  Provider |
                        |   Router  |
                        +-----+-----+
                              |
                              |
                              |  Customer
                              |  Internet Connection
                              |
                        +-----v-----+
                        |   IPv6    |
                        |    CE     |
                        |  Router   |
                        +-----+-----+
                              |
                       +----+-+-------+
                       |              |
                       |              |
                   +---+----+   +-----+------+
                   |  IPv6  |   |            |
                   |  Host  |   |  Router    |
                   |        |   |            |
                   +--------+   +------------+

5.  Requirements

   The IPv6 CE Router distributes configuration information obtained
   during WAN interface provisioning to IPv6 hosts and routers.  A
   router based on [RFC7084] previously would only address IPv6 hosts,
   this update to allow for addressing and routing of routers.

Winters                 Expires 11 September 2023               [Page 3]
Internet-Draft    IPv6 CE Routers LAN Prefix Delegation       March 2023

   LAN Prefix Delegation (PD) Requirements

   LPD-1: The IPv6 CE Router MUST support DHCPv6 server capable of IPv6
   prefix assignment according to [RFC8415] (Idenity Association for
   Prefix Delegation (IA_PD) option).

   LPD-2: The IPv6 CE Router MUST assign addresses from the delegated
   prefix to the number of links.  If not enough addresses are available
   the IPv6 CE Router SHOULD log a system management error.

   LPD-3: The assigned addresses to a link do not change in the absence
   of topology or configuration changes.

   LPD-4: After interface address assignment the IPv6 CE Router MUST
   make the remaining IPv6 prefixes available to other Routers via
   Prefix Delegation

   LPD-5: The IPv6 CE Router MUST give out a IA_PD of the remaining
   prefixes with a IA_PD size of 64.

   LPD-6: The IPv6 CE Router MUST install a route to the IA_PD assigned
   with a next-hop of the IPv6 node assigned the address.  The IPv6 CE
   Router MUST remove a route when IA_PD lease expires as well.

   LPD-7: The IPv6 CE Router firewall MUST allow traffic for Delegated
   Prefixes thru from WAN to LAN.

   LPD-8: If a IPv6 CE Router recieves IPv6 prefixes of size 64 it MUST
   enable delegating relay according to [RFC8987] and the following
   requirements G-2 to G-7, G-9 and S-2.

6.  Security Considerations

   This document does not add any new security considerations beyond
   those mentioned in Section 4 of [RFC8213] and Section 22 of
   [RFC8415].

7.  IANA Considerations

   This document makes no request of IANA.

8.  Acknowledements

   Thanks to the following people for their guidance and feedback:
   Marion Dillon, Erik Auerswald, Esko Dijk, Ted Lemon, Michael
   Richardson, Martin Hunek.

9.  References

Winters                 Expires 11 September 2023               [Page 4]
Internet-Draft    IPv6 CE Routers LAN Prefix Delegation       March 2023

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC6177]  Narten, T., Huston, G., and L. Roberts, "IPv6 Address
              Assignment to End Sites", BCP 157, RFC 6177,
              DOI 10.17487/RFC6177, March 2011,
              <https://www.rfc-editor.org/info/rfc6177>.

   [RFC7084]  Singh, H., Beebee, W., Donley, C., and B. Stark, "Basic
              Requirements for IPv6 Customer Edge Routers", RFC 7084,
              DOI 10.17487/RFC7084, November 2013,
              <https://www.rfc-editor.org/info/rfc7084>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8213]  Volz, B. and Y. Pal, "Security of Messages Exchanged
              between Servers and Relay Agents", RFC 8213,
              DOI 10.17487/RFC8213, August 2017,
              <https://www.rfc-editor.org/info/rfc8213>.

   [RFC8415]  Mrugalski, T., Siodelski, M., Volz, B., Yourtchenko, A.,
              Richardson, M., Jiang, S., Lemon, T., and T. Winters,
              "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)",
              RFC 8415, DOI 10.17487/RFC8415, November 2018,
              <https://www.rfc-editor.org/info/rfc8415>.

   [RFC8987]  Farrer, I., Kottapalli, N., Hunek, M., and R. Patterson,
              "DHCPv6 Prefix Delegating Relay Requirements", RFC 8987,
              DOI 10.17487/RFC8987, February 2021,
              <https://www.rfc-editor.org/info/rfc8987>.

9.2.  Informative References

   [RFC7695]  Pfister, P., Paterson, B., and J. Arkko, "Distributed
              Prefix Assignment Algorithm", RFC 7695,
              DOI 10.17487/RFC7695, November 2015,
              <https://www.rfc-editor.org/info/rfc7695>.

Author's Address

Winters                 Expires 11 September 2023               [Page 5]
Internet-Draft    IPv6 CE Routers LAN Prefix Delegation       March 2023

   Timothy Winters
   QA Cafe
   100 Main Street, Suite #212
   Dover, NH 03820
   United States of America
   Email: tim@qacafe.com

Winters                 Expires 11 September 2023               [Page 6]