Internet Engineering Task Force D. Freedman Internet-Draft Claranet Intended status: Informational M. Townsley Expires: January 26, 2012 Cisco July 25, 2011 IPv6 6RD IPCP configuration option for PPP draft-freedman-pppext-ipv6-6rd-00 Abstract The Point-to-Point Protocol (PPP) (RFC1661) provides a standard method for transporting multi-protocol datagrams over point-to-point links. PPP defines an extensible Link Control Protocol and a family of Network Control Protocols (NCPs) for establishing and configuring different network-layer protocols. This document extends the NCP for establishing and configuring the Internet Protocol over PPP (RFC1332), defining the negotiation of 6RD (RFC5969) Border Relay (BR) addresses. While the authors believe one could use DHCP INFORM (RFC2131) to obtain the necessary 6RD parameters, this is simply an alternative which allows reuse of an existing PPP-based configuration infrastructure. 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 http://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 January 26, 2012. Copyright Notice Copyright (c) 2011 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 Freedman & Townsley Expires January 26, 2012 [Page 1] Internet-Draft 6RD IPCP configuration option July 2011 Provisions Relating to IETF Documents (http://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 Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. 6RD IPCP configuration option . . . . . . . . . . . . . . . . 5 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7.1. Normative References . . . . . . . . . . . . . . . . . . . 10 7.2. Informational References . . . . . . . . . . . . . . . . . 10 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11 Freedman & Townsley Expires January 26, 2012 [Page 2] Internet-Draft 6RD IPCP configuration option July 2011 1. Introduction PPP [RFC1661], and PPPoE [RFC2516], remains a common way for a residential broadband end user to obtain configuration. In such deployments, no DHCP [RFC2131], infrastructure may be in place and IP configuration is solely obtained from RADIUS [RFC2865] servers and network equipment via IPCP [RFC1332]. The PPP IPCP option presents configuration information to the local peer such that it may join a 6RD [RFC5969] domain. Freedman & Townsley Expires January 26, 2012 [Page 3] Internet-Draft 6RD IPCP configuration option July 2011 2. Terminology 6RD IPv6 Prefix An IPv6 prefix selected by the service provider for use by a 6RD domain. There is exactly one 6RD IPv6 prefix for a given 6RD domain. An SP may deploy 6RD with a single 6RD domain or multiple 6RD domains. 6RD Delegated Prefix The IPv6 prefix calculated by the local peer for use within the customer site by combining the 6RD prefix and the local peer IPv4 address obtained via IPv4 configuration methods. This prefix can be considered logically equivalent to a DHCPv6 IPv6 delegated prefix [RFC3633]. 6RD Domain A service provider may deploy 6RD with a single 6RD domain, or may utilize multiple 6RD domains. Each domain requires a seperate 6RD IPv6 prefix. 6RD Border Relay (BR) A 6RD-enabled router managed by the service provider at the edge of a 6RD domain. A Border Relay router provides an endpoint for the 6RD IPv6 in IPv4 tunnel. A 6RD BR may also be referred to simply as a "BR" within the context of 6RD. 6RD BR address The IPv4 address of the 6RD Border Relay for a given 6RD domain. This IPv4 address is used by the local peer to send packets to a BR in order to reach IPv6 destinations outside of the 6RD domain. Freedman & Townsley Expires January 26, 2012 [Page 4] Internet-Draft 6RD IPCP configuration option July 2011 3. 6RD IPCP configuration option Description: This Configuration Option provides a method for informing the local peer of the configuration parameters required for the 6RD domain available for the peer to join. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | type | length |V4Prefix-Length|V6Prefix-Length| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 6RD BR Address (4 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | 6RD IPv6 Prefix | | (variable, up to 16 octets) | | | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1 Type: TBA Length: The total length of the IPCP option, in octets V4Prefix-Length Prefix length of the common part of the encoded IPv4 address in number of bits. This number of bits MUST be removed from leftmost of the IPv4 address when generating the 6RD Delegated Prefix. For example, if this value is 8, 24 bits of the subscriber IPv4 prefix will be used when creating the IPv6 Delegated Prefix, determining the destination IPv4 encapsulation address, etc. If the value is 0, then the whole 32 bits of the IPv4 address is used in the encoding. Freedman & Townsley Expires January 26, 2012 [Page 5] Internet-Draft 6RD IPCP configuration option July 2011 V6Prefix-Length IPv6 Prefix length of the 6RD IPv6 prefix in number of bits. 6RD BR Address The IPv4 address of the 6RD Relay (may be anycast) 6RD IPv6 prefix The service provider's 6RD IPv6 prefix represented as a 16-octet IPv6 address. Default: By default, no fields are populated Freedman & Townsley Expires January 26, 2012 [Page 6] Internet-Draft 6RD IPCP configuration option July 2011 4. IANA Considerations This memo requires an IPCP option number assignment. Freedman & Townsley Expires January 26, 2012 [Page 7] Internet-Draft 6RD IPCP configuration option July 2011 5. Security Considerations This memo does not present any security considerations, it is assumed that the remote peer is trusted and therefore the parameters of the 6RD domain are to be trusted. Freedman & Townsley Expires January 26, 2012 [Page 8] Internet-Draft 6RD IPCP configuration option July 2011 6. Acknowledgements This memo is based on existing work [I-D.townsley-ipv6-6rd] which describes possible provisioning of 6RD configuration parameters. Freedman & Townsley Expires January 26, 2012 [Page 9] Internet-Draft 6RD IPCP configuration option July 2011 7. References 7.1. Normative References [RFC1332] McGregor, G., "The PPP Internet Protocol Control Protocol (IPCP)", RFC 1332, May 1992. [RFC1661] Simpson, W., "The Point-to-Point Protocol (PPP)", STD 51, RFC 1661, July 1994. [RFC2516] Mamakos, L., Lidl, K., Evarts, J., Carrel, D., Simone, D., and R. Wheeler, "A Method for Transmitting PPP Over Ethernet (PPPoE)", RFC 2516, February 1999. [RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6", RFC 3633, December 2003. [RFC5969] Townsley, W. and O. Troan, "IPv6 Rapid Deployment on IPv4 Infrastructures (6rd) -- Protocol Specification", RFC 5969, August 2010. 7.2. Informational References [I-D.townsley-ipv6-6rd] Townsley, M. and O. Troan, "IPv6 via IPv4 Service Provider Networks", draft-townsley-ipv6-6rd-01 (work in progress), July 2009. [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997. [RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson, "Remote Authentication Dial In User Service (RADIUS)", RFC 2865, June 2000. Freedman & Townsley Expires January 26, 2012 [Page 10] Internet-Draft 6RD IPCP configuration option July 2011 Authors' Addresses David Freedman Claranet London UK Phone: +44 20 7685 8000 Email: david.freedman@uk.clara.net Mark Townsley Cisco Systems Paris France Phone: +33 15 804 3483 Email: mark@townsley.net Freedman & Townsley Expires January 26, 2012 [Page 11]