Network Working Group B. Sarikaya Internet-Draft Huawei USA Intended status: Standards Track February 25, 2013 Expires: August 29, 2013 IPv6 RA Options for Translation Multicast Prefixes draft-sarikaya-softwire-6man-raoptions-01 Abstract This draft defines new Router Advertisement options for configuring multicast prefixes and unicast prefixes for multicast source addresses. Each option is defined together with definitions of host and router behaviors. 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 August 29, 2013. Copyright Notice Copyright (c) 2013 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 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Sarikaya Expires August 29, 2013 [Page 1] Internet-Draft New RA Options February 2013 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Multicast Translation Prefixes Configuration . . . . . . . . . 3 4. Multicast Translation Prefix Options . . . . . . . . . . . . . 4 5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 7 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 8.1. Normative References . . . . . . . . . . . . . . . . . . . 8 8.2. Informative References . . . . . . . . . . . . . . . . . . 9 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 10 Sarikaya Expires August 29, 2013 [Page 2] Internet-Draft New RA Options February 2013 1. Introduction IPv6 Neighbor Discovery and IPv6 Stateless Address Autoconfiguration protocols can be used to configure fixed and mobile nodes with various parameters related to addressing and routing [RFC4861], [RFC4862], and [RFC4191]. DNS Recursive Server Addresses and Domain Name Search Lists are additional parameters that can be configured using router advertisements [RFC6106]. In multicast IPv4 to IPv6 transition technologies, specific IPv6 addresses are used in which IPv4 addresses are embedded [RFC6180]. Some of these addresses are multicast IPv6 addresses and some are unicast. Both multicast and unicast addresses can be generated from the corresponding multicast and unicast prefixes. These prefixes must be provisioned on the hosts that are involved in translation. 2. Terminology 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 [RFC2119]. 3. Multicast Translation Prefixes Configuration A host wishing to join a source-specific multicast (SSM) group sends an IGMP Membership Report message and includes the group address in Multicast Address field of Group Record field in IPv4 [RFC3376]. Multicast group address MUST be a multicast group address in SSM range. In IPv4 to IPv6 transition scenarios, IGMP membership Report message must be translated into MLD Membership Report message [RFC3810], usually at the IGMP/MLD proxy entity [RFC4605]. SSM group is identified with a group and source address in (S,G) form. The source address is specified in Source Address field of Group Record field in IGMP Membership Report message. There could be more than one source addresses associated with one Multicast Address. IGMP to MLD translation entity must be configured with an IPv6 multicast group prefix that is in SSM range. [I-D.ietf-mboned-64-multicast-address-format] defines multicast prefixes (MPREFIX64) for IPv4-embedded IPv6 multicast address based on an IPv4 multicast address of two types: ASM_MPREFIX64 for any- source multicast (ASM) and SSM_MPREFIX64 for source-specific multicast (SSM). IGMP to MLD translation entity can be configured with SSM_MPREFIX64 by its default router if the default router includes in its Router Sarikaya Expires August 29, 2013 [Page 3] Internet-Draft New RA Options February 2013 Advertisements a Multicast SSM Translation Prefix option defined in Figure 1. SSM_MPREFIX64 is of type ff3x:0:8000/33. Prefix length MAY be set to 96. IGMP to MLD translation entity can be configured with ASM_MPREFIX64 by its default router if the default router includes in its Router Advertisements a Multicast ASM Translation Prefix option defined in Figure 2. ASM_MPREFIX64 is of type ffxx:8000/17. Prefix length MAY be set to 96. SSM groups have one or more sources, S in (S,G). The source address is specified by the joining host in IGMP Membership Report message's Source Address field of Group Record. IPv4 source address in IGMP Membership Report message needs to be translated into an IPv6 source address in the translated MLD message. IGMP to MLD translation entity can be configured with U_PREFIX64 by its default router if the default router includes in its Router Advertisements a Multicast Translation Unicast Prefix option defined in Figure 3. U_PREFIX64 could be assigned to 64:ff9b::/96 which is known as the well-known prefix or to some operator specific value. Prefix length MAY be set to 96. IPv4-Embedded IPv6 Unicast Addresses MUST be formed using the rules defined in [RFC6052]. U_PREFIX64 MUST also be used in translating IPv4 multicast data packets from SSM sources, S of (S,G) into IPv6 multicast data packets. In this case the translation entity is connected to IPv4 network at the border of an IPv6 network, e.g. Border Router (BR). Border Router MUST also be configured with U_PREFIX64 by its default router if the default router includes in its Router Advertisements a Multicast Translation Unicast Prefix option defined in Figure 3. Multicast translation prefixes may be configured using DHCPv6. In some networks, DHCPv6 is not used such as in 3GPP networks. RA based solution presented in this document can be used when DHCPv6 is not configured or used. Also it could be advantageous to use RA based solution for some operators. 4. Multicast Translation Prefix Options In this section we define three prefix options that are related to the translation of IGMP messages into MLD or vice versa. Figure 1 defines Source Specific Multicast translation prefix option commonly known as SSM_PREFIX64. It is an IPv6 prefix belonging to source specific multicast (ssm) range with a value similar to ff3x:0: 8000/33. It is used in embedding IPv4 SSM range multicast addresses. Sarikaya Expires August 29, 2013 [Page 4] Internet-Draft New RA Options February 2013 The values MUST conform to [I-D.ietf-mboned-64-multicast-address-format]. Figure 2 defines Any Source Multicast translation prefix option commonly known as ASM_PREFIX64. It is an IPv6 prefix belonging to any source multicast (asm) range with a value similar to ffxx: 8000/17. It is used in embedding IPv4 ASM range multicast addresses. The values MUST conform to [I-D.ietf-mboned-64-multicast-address-format] Figure 3 defines Multicast Translation Unicast prefix option commonly known as U_PREFIX64. It is an IPv6 unicast prefix It is used in translating IPv4 source addresses into IPv6 source address or vice versa for source specific multicast sources. [RFC6052] defines two types for U_PREFIX_64, well known prefix of 64:ff9b::/96 or the network specific prefix and the mapping rules from IPv4 to IPv6 address and vice versa. 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 |Prefix Length | Reserved1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SSM_MPREFIX64 Prefix | . . . . +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Multicast SSM Translation Prefix option Fields: Type: TBD. Length: The length of the option (including the type and length fields) in units of 8 octets. For example, the length for an IPv6 address is 3. Prefix Length: 8-bit unsigned integer. The number of leading bits in the Prefix that are valid. The value ranges from 0 to 128. Reserved1 8-bit unused field. It MUST be initialized to zero by the sender and MUST be ignored by the receiver. Reserved2 32-bit unused field. It MUST be initialized to zero by the sender and MUST be ignored by the receiver. Sarikaya Expires August 29, 2013 [Page 5] Internet-Draft New RA Options February 2013 Prefix: A prefix of type source specific multicast. The Prefix Length field contains the number of valid leading bits in the prefix. The bits in the prefix after the prefix length are reserved and MUST be initialized to zero by the sender and ignored by the receiver. 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 |Prefix Length | Reserved1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ASM_MPREFIX64 Prefix | . . . . +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: Multicast ASM Translation Prefix option Fields: Type: TBD. Length and other fields are as defined above. 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 |Prefix Length | Reserved1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | U_PREFIX64 Prefix | . . . . +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: Multicast Translation Unicast Prefix option Fields: Type: TBD. Length and other fields are as defined above. Sarikaya Expires August 29, 2013 [Page 6] Internet-Draft New RA Options February 2013 5. Security Considerations Neighbor Discovery is subject to attacks that cause IP packets to flow to unexpected places. Because of this, neighbor discovery messages MUST be secured, possibly using Secure Neighbor Discovery (SEND) protocol [RFC3971]. 6. IANA Considerations Authors of this document request IANA to assign six new RA options: Option Name Type Route Prefix option Option Name Type Next Hop Address option Option Name Type Next Hop Address and Route Prefix option Option Name Type Multicast SSM Translation Prefix option Option Name Type Multicast ASM Translation Prefix option Option Name Type Multicast Translation Unicast Prefix option 7. Acknowledgements TBD. Sarikaya Expires August 29, 2013 [Page 7] Internet-Draft New RA Options February 2013 8. References 8.1. Normative References [I-D.ietf-mboned-64-multicast-address-format] Boucadair, M., Qin, J., Lee, Y., Venaas, S., Li, X., and M. Xu, "IPv6 Multicast Address With Embedded IPv4 Multicast Address", draft-ietf-mboned-64-multicast-address-format-04 (work in progress), August 2012. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629, June 1999. [RFC3376] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A. Thyagarajan, "Internet Group Management Protocol, Version 3", RFC 3376, October 2002. [RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, June 2004. [RFC3971] Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure Neighbor Discovery (SEND)", RFC 3971, March 2005. [RFC4191] Draves, R. and D. Thaler, "Default Router Preferences and More-Specific Routes", RFC 4191, November 2005. [RFC4605] Fenner, B., He, H., Haberman, B., and H. Sandick, "Internet Group Management Protocol (IGMP) / Multicast Listener Discovery (MLD)-Based Multicast Forwarding ("IGMP/MLD Proxying")", RFC 4605, August 2006. [RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, September 2007. [RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless Address Autoconfiguration", RFC 4862, September 2007. [RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X. Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052, October 2010. Sarikaya Expires August 29, 2013 [Page 8] Internet-Draft New RA Options February 2013 8.2. Informative References [RFC6106] Jeong, J., Park, S., Beloeil, L., and S. Madanapalli, "IPv6 Router Advertisement Options for DNS Configuration", RFC 6106, November 2010. [RFC6180] Arkko, J. and F. Baker, "Guidelines for Using IPv6 Transition Mechanisms during IPv6 Deployment", RFC 6180, May 2011. Sarikaya Expires August 29, 2013 [Page 9] Internet-Draft New RA Options February 2013 Author's Address Behcet Sarikaya Huawei USA Plano, TX 75075 Phone: +1 972-509-5599 Email: sarikaya@ieee.org Sarikaya Expires August 29, 2013 [Page 10]