v6ops WG S. Gundavelli Internet-Draft M. Townsley Updates: 2464 (if approved) O. Troan Intended status: Standards Track W. Dec Expires: April 16, 2011 Cisco October 13, 2010 Address Mapping of IPv6 multicast packets on Ethernet draft-gundavelli-v6ops-l2-unicast-05.txt Abstract When transmitting an IPv6 packet with a multicast destination address, the IPv6 destination address is mapped to an Ethernet link- layer multicast address. This document clarifies that a mapping of an IPv6 packet with a multicast destination address may in some circumstances map to an Ethernet link-layer unicast address. 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 April 16, 2011. Copyright Notice Copyright (c) 2010 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 (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 Gundavelli, et al. Expires April 16, 2011 [Page 1] Internet-Draft Unicast Transmission on Link-layer October 2010 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Gundavelli, et al. Expires April 16, 2011 [Page 2] Internet-Draft Unicast Transmission on Link-layer October 2010 1. Introduction Transmission of IPv6 Packets over Ethernet [RFC2464] section 7, specifies how an IPv6 packet with a multicast destination address is mapped into an Ethernet link-layer address. This document extends this mapping to explicitly allow for a mapping of an IPv6 packet with a multicast destination address into an Ethernet link-layer unicast address, when it is clear that only one address is relevant. This mapping does not replace the mapping described in [RFC2464] section 7. Sending a targeted multicast packet, i.e. sending an IPv6 packet with a multicast destination address to an Ethernet link-layer unicast address, is only reasonable if the unicast address is known and is reasonably believed to be the only address relevant. The determination of the unicast Ethernet link-layer address and the construction of the outgoing IPv6 packet are out of scope for this document. Gundavelli, et al. Expires April 16, 2011 [Page 3] Internet-Draft Unicast Transmission on Link-layer October 2010 2. Conventions 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 [RFC2119]. Gundavelli, et al. Expires April 16, 2011 [Page 4] Internet-Draft Unicast Transmission on Link-layer October 2010 3. Sending and receiving IPv6 multicast packets The following additional considerations apply to all IPv6 nodes when sending and receiving IPv6 multicast messages. o An IPv6 node transmitting an IPv6 packet with a multicast destination address MAY use a unicast Ethernet link-layer address. o An IPv6 node receiving an IPv6 packet with a multicast destination address and an Ethernet link-layer unicast address MUST NOT drop the packet as a result of the use of this form of address mapping. Gundavelli, et al. Expires April 16, 2011 [Page 5] Internet-Draft Unicast Transmission on Link-layer October 2010 4. IANA Considerations This specification does not require any IANA actions. Gundavelli, et al. Expires April 16, 2011 [Page 6] Internet-Draft Unicast Transmission on Link-layer October 2010 5. Security Considerations This document does not introduce any new security vulnerabilities. Gundavelli, et al. Expires April 16, 2011 [Page 7] Internet-Draft Unicast Transmission on Link-layer October 2010 6. Acknowledgements The authors would like to acknowledge Bernard Aboba, Fred Baker, Wes Beebee, Ron Bonica, Olaf Bonness, Jean-Michel Combes, Ralph Droms, Alain Durand, Suresh Krishnan, Eric Levy-Abegnoli, Phil Roberts, Behcet Sarikaya, Hemant Singh, Mark Smith, Dave Thaler, Pascal Thubert, Stig Venaas and Eric Voit for their contributions and discussions on this topic. Gundavelli, et al. Expires April 16, 2011 [Page 8] Internet-Draft Unicast Transmission on Link-layer October 2010 7. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet Networks", RFC 2464, December 1998. Gundavelli, et al. Expires April 16, 2011 [Page 9] Internet-Draft Unicast Transmission on Link-layer October 2010 Authors' Addresses Sri Gundavelli Cisco 170 West Tasman Drive San Jose, CA 95134 USA Email: sgundave@cisco.com Mark Townsley Cisco L'Atlantis, 11, Rue Camille Desmoulins ISSY LES MOULINEAUX, ILE DE FRANCE 92782 France Email: townsley@cisco.com Ole Troan Cisco Oslo, Norway Email: ot@cisco.com Wojciech Dec Cisco Haarlerbergweg 13-19 Amsterdam, Noord-Holland 1101 CH Netherlands Email: wdec@cisco.com Gundavelli, et al. Expires April 16, 2011 [Page 10]