INTERNET-DRAFT Link-Layer Option Extension S. Goswami Expires June 21, 2002 Self Inc Dec 21, 2001 IPv6 Neighbor Discovery Link-Layer Option Extension 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-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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. 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 RFC 2119 [RFC 2119]. Abstract This document describes changes to the Source/Target Link-layer Address option in IPv6 Neighbor Discovery Protocol [IPv6ND] to support addresses of any liength. 1. Overview and Rationale The IPv6 Neighbor Disocvery Protocol uses Link-Layer addresses in option. The option as it stands can only support link layer addresses of 6 + 8*n octets, where n is natural number (i.e 0,1,2,3, ...). This precludes the support for link layer addresses of arbitrary length that may need to be supported in the future. One example of such an address is IEEE-EUI64 which is a 8 octet address. 2. Additional Requirements for Link-Layer Options for Neighbor Dicovery This document adds two more option types to be used with Neighbor Discovery. The 4.6.1. Source/Target Any Length Link-layer Address 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 | Link-Layer Address ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Fields: Type 11 for Source Any Length Link-layer Address 12 for Target Any Length Link-layer Address Length The length of the option (including the type and length fields) in units of 1/8 th octets. Forexample, the length for IEEE 802 addresses is 1 [IPv6- ETHER]. Link-Layer Address The variable length link-layer address. The content and format of this field (including byte and bit ordering) is expected to be specified in specific documents that describe how IPv6 operates over different link layers. For instance, [IPv6-ETHER]. Description The Source Link-Layer Address option contains the link-layer address of the sender of the packet. It is used in the Neighbor Solicitation, Router Solicitation, and Router Advertisement packets. The Target Link-Layer Address option contains the link-layer address of the target. It is used in Neighbor Advertisement and Redirect packets. These options MUST be silently ignored for other Neighbor Discovery messages. 2.2 Router Solicitation Message In addition to the options mentioned in [IPV6ND], the Source Any Length Link-layer Address can be used. 2.3 Router Advertisement Message In addition to the options mentioned in [IPV6ND], the Source Any Length Link-layer Address can be used. 2.4 Neighbor Solicitation Message In addition to the options mentioned in [IPV6ND], the Source Any Length Link-layer Address can be used. 2.5 Neighbor Advertisement Message In addition to the options mentioned in [IPV6ND], the Target Any Length Link-layer Address can be used. 2.6 Redirect Message Format In addition to the options mentioned in [IPV6ND], the Target Any Length Link-layer Address can be used. 4. Acknowledgments The authors would like to thank Vince Laviano, Nidhi Bhaskar, and Steve Deering and for their input and careful review. 5. References [IPV6ND] Narten, T, et. al., "Neighbor Discovery for IP Version 6 (IPv6)", RFC 2461, December 1998. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels," RFC 2119, March 1997. [IANA-ALLOCATION] Internet Assigned Numbers Authority, http://www.isi.edu/in-notes/iana/assignments/multicast-addresses. [IEEE-EUI64] GUIDELINES FOR 64-BIT GLOBAL IDENTIFIER (EUI-64™) REGISTRATION AUTHORITY, http://standards.ieee.org/regauth/oui/tutorials/EUI64.html 6. Author's Address Dr. Subrata Goswami Self Inc. Newark, CA 94560 sgoswami@umich.edu This document expires June 21, 2002.