IP Version 6 over PPP
RFC 5072

Network Working Group                                     S. Varada, Ed.
Request for Comments: 5072                                    Transwitch
Obsoletes: 2472                                               D. Haskins
Category: Standards Track                                       E. Allen
                                                          September 2007

                         IP Version 6 over PPP

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Abstract

   The Point-to-Point Protocol (PPP) provides a standard method of
   encapsulating network-layer protocol information over point-to-point
   links.  PPP also defines an extensible Link Control Protocol, and
   proposes a family of Network Control Protocols (NCPs) for
   establishing and configuring different network-layer protocols.

   This document defines the method for sending IPv6 packets over PPP
   links, the NCP for establishing and configuring the IPv6 over PPP,
   and the method for forming IPv6 link-local addresses on PPP links.

   It also specifies the conditions for performing Duplicate Address
   Detection on IPv6 global unicast addresses configured for PPP links
   either through stateful or stateless address autoconfiguration.

   This document obsoletes RFC 2472.

Varada, et al.              Standards Track                     [Page 1]
RFC 5072                 IP Version 6 over PPP            September 2007

Table of Contents

   1. Introduction ....................................................2
      1.1. Specification of Requirements ..............................3
   2. Sending IPv6 Datagrams ..........................................3
   3. A PPP Network Control Protocol for IPv6 .........................3
   4. IPV6CP Configuration Options ....................................4
      4.1. Interface Identifier .......................................4
   5. Stateless Autoconfiguration and Link-Local Addresses ............9
   6. Security Considerations ........................................11
   7. IANA Considerations ............................................11
   8. Acknowledgments ................................................11
   9. References .....................................................12
      9.1. Normative References ......................................12
      9.2. Informative references ....................................12
   Appendix A:  Global Scope Addresses................................14
   Appendix B:  Changes from RFC-2472.................................14

1.  Introduction

   PPP has three main components:

   1) A method for encapsulating datagrams over serial links.

   2) A Link Control Protocol (LCP) for establishing, configuring, and
      testing the data-link connection.

   3) A family of Network Control Protocols (NCPs) for establishing and
      configuring different network-layer protocols.

   In order to establish communications over a point-to-point link, each
   end of the PPP link must first send LCP packets to configure and test
   the data link.  After the link has been established and optional
   facilities have been negotiated as needed by the LCP, PPP must send
   NCP packets to choose and configure one or more network-layer
   protocols.  Once each of the chosen network-layer protocols has been
   configured, datagrams from each network-layer protocol can be sent
   over the link.

   In this document, the NCP for establishing and configuring the IPv6
   over PPP is referred to as the IPv6 Control Protocol (IPV6CP).

   The link will remain configured for communications until explicit LCP
   or NCP packets close the link down, or until some external event
   occurs (power failure at the other end, carrier drop, etc.).

   This document obsoletes the earlier specification from RFC 2472 [7].
   Changes from RFC 2472 are listed in Appendix B.

Varada, et al.              Standards Track                     [Page 2]
RFC 5072                 IP Version 6 over PPP            September 2007

1.1.  Specification of Requirements

   In this document, several words are used to signify the requirements
   of the specification.

   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 [6].