Internet-Draft K. Fujisawa <draft-fujisawa-ip1394-ipv6-02.txt> Sony Corporation Expires: August, 1999 February 1999 Transmission of IPv6 Packets over IEEE 1394 Networks 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. Abstract IEEE Std 1394-1995 is a standard for a High Performance Serial Bus. This document proposes the frame format for transmission of IPv6 [IPV6] packets and the method of forming IPv6 link-local addresses and statelessly autoconfigured addresses on IEEE1394 networks. It also proposes the content of the Source/Target Link-layer Address option used in Neighbor Discovery [DISC] when the messages are transmitted on an IEEE1394 network. K. Fujisawa Expires August 1999 [Page 1]
Internet Draft draft-fujisawa-ip1394-ipv6-02.txt February 1999 1. INTRODUCTION IEEE Std 1394-1995 is a standard for a High Performance Serial Bus. IETF IP1394 Working Group is standardizing the method to carry IPv4 datagrams and ARP packets over IEEE1394 subnetwork [IP1394]. This document proposes the frame format for transmission of IPv6 [IPV6] packets and the method of forming IPv6 link-local addresses and statelessly autoconfigured addresses on IEEE1394 networks. It also proposes the content of the Source/Target Link-layer Address option used in Neighbor Discovery [DISC] when the messages are transmitted on an IEEE1394 network. 2. SPECIFICATION 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 RFC 2119. 3. IPv6-CAPABLE NODES An IPv6-capable node SHALL fulfill the following minimum requirements; - it SHALL implement configuration ROM in the general format specified by ISO/IEC 13213:1994 and SHALL implement the bus information block specified by IEEE P1394a [P1394a] and a unit directory specified by this memo; - the max_rec field in its bus information block SHALL be at least 8; this indicates an ability to accept block write requests and asynchronous stream packets with data payload of 512 octets. The same ability SHALL also apply to read requests; that is, the node SHALL be able to transmit a block response packet with a data payload of 512 octets; - it SHALL be isochronous resource manager capable, as specified by 1394; - it SHALL support both reception and transmission of asynchronous streams as specified by IEEE P1394a; - it SHALL implement the BROADCAST_CHANNEL register as specified by IEEE P1394a; and - it SHALL be broadcast channel manager capable. 4. LINK ENCAPSULATION AND FRAGMENTATION K. Fujisawa Expires August 1999 [Page 2]
Internet Draft draft-fujisawa-ip1394-ipv6-02.txt February 1999 The encapsulation and fragmentation mechanism SHOULD be the same as "5. LINK ENCAPSULATION AND FRAGMENTATION" of [IP1394]. The ether_type value for IPv6 is 0x86dd. The default MTU size for IPv6 packets on an IEEE1394 network is 1500 octets. This size may be reduced by a Router Advertisement [DISC] containing an MTU option which specifies a smaller MTU, or by manual configuration of each node. If a Router Advertisement received on an IEEE1394 interface has an MTU option specifying an MTU larger than 1500, or larger than a manually configured value, that MTU option may be logged to system management but MUST be otherwise ignored. The mechanism to extend MTU size between particular two nodes is for further study. 5. CONFIGURATION ROM Configuration ROM for IPv6-capable nodes SHALL contain a unit directory in the format specified by [IP1394] except following rules. - The value for Unit_SW_Version is TBD. When this draft is approved it is EXPECTED that Unit_SW_Version will assume the value of the RFC number assigned. - The textual descriptor for the Unit_SW_Version SHOULD be "IPv6". 6. STATELESS AUTOCONFIGURATION The Interface Identifier [AARCH] for an IEEE1394 interface is formed from the interface's built-in EUI-64 by complementing the "Universal/Local" (U/L) bit, which is the next-to-lowest order bit of the first octet of the EUI-64. Complementing this bit will generally change a 0 value to a 1, since an interface's built-in address is expected to be from a universally administered address space and hence have a globally unique value. A universally administered EUI- 64 is signified by a 0 in the U/L bit position, while a globally unique IPv6 Interface Identifier is signified by a 1 in the corresponding position. For further discussion on this point, see [AARCH]. An IPv6 address prefix used for stateless autoconfiguration [ACONF] of an IEEE1394 interface MUST have a length of 64 bits. 7. LINK-LOCAL ADDRESSES The IPv6 link-local address [AARCH] for an IEEE1394 interface is formed by appending the Interface Identifier, as defined above, to the prefix FE80::/64. K. Fujisawa Expires August 1999 [Page 3]
Internet Draft draft-fujisawa-ip1394-ipv6-02.txt February 1999 10 bits 54 bits 64 bits +----------+-----------------------+----------------------------+ |1111111010| (zeros) | Interface Identifier | +----------+-----------------------+----------------------------+ 8. ADDRESS MAPPING FOR UNICAST The procedure for mapping IPv6 unicast addresses into IEEE1394 link- layer addresses uses the Neighbor Discovery [DISC]. Since 1394 link address (node_ID) will not be constant across a 1394 bridge, we have chosen not to put it in the Link-layer Address option. The recipient of the Neighbor Discovery SHALL use the source_node_ID in the 1394 packet header or GASP header in conjunction with the content of the Source link-layer address. The Source/Target Link-layer Address option has the following form when the link layer is IEEE1394. 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 = 3 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ---+ | node_unique_ID | +--- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | max_rec | spd | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | unicast_FIFO | +--- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type 1 for Source Link-layer address. 2 for Target Link-layer address. Length 3 (in units of 8 octets). The meaning of 'node_unique_ID', 'unicast_FIFO', 'max_rec' and 'spd' sub-fields are specified in [IP1394]. Note that node_ID may change when 1394 bus-reset occurs. The mapping cache held in the node SHOULD be cleared on 1394 bus-reset. 9. IPv6 MULTICAST By default, all best-effort IPv6 multicast SHALL use asynchronous stream packets whose channel number is equal to the channel field K. Fujisawa Expires August 1999 [Page 4]
Internet Draft draft-fujisawa-ip1394-ipv6-02.txt February 1999 from the BROADCAST_CHANNEL register. Best-effort IPv6 multicast for particular multicast group addresses may utilize a different channel number if such a channel number is allocated and advertised prior to use, by the multicast channel allocation protocol (MCAP), as described in [IP1394]. The 'type' field in MCAP group address descriptor SHALL be TBD to indicate an IPv6 group address descriptor. 10. OPEN ISSUES a) The mechanism to extend MTU size between particular two nodes. b) The mechanism to allocate and distribute a 1394 isochronous channel number for isochronous transmission of IPv6 packets, for an unicast or multicast flow. Security Considerations Security issues are not discussed in this document. Acknowledgement The auther would like to acknowledge the author of [ETHER] since some part of this document has been derived from [ETHER]. References [1394] IEEE Std 1394-1995, Standard for a High Performance Serial Bus [P1394a] IEEE Project P1394a, Draft Standard for a High Performance Serial Bus (Supplement) [CSR] ISO/IEC 13213:1994, Control and Status Register (CSR) Architecture for Microcomputer Buses [IP1394] IP1394 Working Group, "IPv4 over IEEE 1394", currently draft-ietf-ip1394-ipv4-13.txt. [IPV6] S. Deering, R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", RFC2460, Dec 1998. [AARCH] R. Hinden, S. Deering "IP Version 6 Addressing Architecture", RFC2373. [ACONF] S. Thomson, T. Narten, "IPv6 Stateless Address Autoconfiguration", RFC2462, Dec 1998. K. Fujisawa Expires August 1999 [Page 5]
Internet Draft draft-fujisawa-ip1394-ipv6-02.txt February 1999 [DISC] T. Narten, E. Nordmark, W. A. Simpson, "Neighbor Discovery for IP Version 6 (IPv6)", RFC2461, Dec 1998. [ETHER] M. Crawford, "Transmission of IPv6 Pacekts over Ethernet Networks", RFC2464, Dec 1998. Author's address Kenji Fujisawa Sony Corporation IT Laboratories, Computer Systems Laboratory 6-7-35, Kitashinagawa, Shinagawa-ku, Tokyo, 141-0001 Japan Phone: +81-3-5448-4602 E-mail: fujisawa@sm.sony.co.jp Technical changes from old version * Changes from -00.txt - Two octets padding in a Source/Target Link-layer Address option of the Neighbor Discovery has been removed. * Changes from -01.txt - The 'node_ID' sub field has been removed from a Source/Target Link-layer Address option of the Neighbor Discovery, and the order of some fields has been changed in accordance with [IP1394]. - The MCAP type value for IPv6 group address descriptor is changed to TBD. - A new section for "CONFIGURATION ROM" has been added. K. Fujisawa Expires August 1999 [Page 6]