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Network Working Group                                        K. FujisawaRequest for Comments: 3146                                       A. OnoeCategory: Standards Track                               Sony Corporation                                                            October 2001Transmission of IPv6 Packets over IEEE 1394 NetworksStatus of this Memo   This document specifies an Internet standards track protocol for the   Internet community, and requests discussion and suggestions for   improvements.  Please refer to the current edition of the "Internet   Official Protocol Standards" (STD 1) for the standardization state   and status of this protocol.  Distribution of this memo is unlimited.Copyright Notice   Copyright (C) The Internet Society (2001).  All Rights Reserved.Abstract   This document describes the frame format for transmission of IPv6   packets and the method of forming IPv6 link-local addresses and   statelessly autoconfigured addresses on IEEE1394 networks.1. INTRODUCTION   IEEE Std 1394-1995 (and its amendment) is a standard for a High   Performance Serial Bus.  IETF IP1394 Working Group has standardized   the method to carry IPv4 datagrams and ARP packets over IEEE1394   subnetwork [IP1394].   This document describes 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 describes 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 inRFC 2119.Fujisawa & Onoe             Standards Track                     [Page 1]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 20013. IPv6-CAPABLE NODES   An IPv6-capable node MUST fulfill the following minimum requirements:   -  it MUST implement configuration ROM in the general format      specified by ISO/IEC 13213:1994 and MUST implement the bus      information block specified by IEEE Std 1394a-2000 [1394a] and a      unit directory specified by this document;   -  the max_rec field in its bus information block MUST 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 MUST also apply to read requests; that is, the node      MUST be able to transmit a block response packet with a data      payload of 512 octets;   -  it MUST be isochronous resource manager capable, as specified by      IEEE Std 1394a-2000;   -  it MUST support both reception and transmission of asynchronous      streams as specified by IEEE Std 1394a-2000.4. LINK ENCAPSULATION AND FRAGMENTATION   The encapsulation and fragmentation mechanism MUST be the same as "4.   LINK ENCAPSULATION AND FRAGMENTATION" of [IP1394].      Note: Since there is an ether_type field to discriminate protocols      and MCAP (multicast channel allocation protocol) is used for both      IPv4 and IPv6, the version field in GASP (global asynchronous      stream packet) header of IPv6 datagrams is the same value (one) as      [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.Fujisawa & Onoe             Standards Track                     [Page 2]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 20015. CONFIGURATION ROM   Configuration ROM for IPv6-capable nodes MUST contain a unit   directory in the format specified by [IP1394] except following rules.   - The value for Unit_SW_Version is 0x000002.   - The textual descriptor for the Unit_SW_Version MUST be "IPv6".      Note: A dual-stack (IPv4 and IPv6) node will have two unit      directories for IPv4 and IPv6 respectively.6. STATELESS AUTOCONFIGURATION   The Interface Identifier [AARCH] for an IEEE1394 interface is formed   from the interface's built-in EUI-64 identifier by complementing the   "Universal/Local" (U/L) bit, which is the next-to-lowest order bit of   the first octet of the EUI-64 identifier.  Complementing this bit   will generally change a 0 value to a 1, since an interface's built-in   EUI-64 identifier is expected to be from a universally administered   address space and hence have a globally unique value.  A universally   administered EUI-64 identifier 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.     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 SHOULD use the source_ID (obtained from   either the asynchronous packet header or the GASP header) inFujisawa & Onoe             Standards Track                     [Page 3]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 2001   conjunction with the content of the Source link-layer address.  An   implementation MAY use some other methods to obtain a node_ID of the   sender utilizing a mapping table between node_unique_ID (EUI-64   identifier) and node_ID.  The mechanism to make such mapping table is   out of scope of this document.   The recipient of an Neighbor Discovery packet MUST ignore it unless   the most significant ten bits of the source_ID are equal to either   0x3FF or the most significant ten bits of the recipient's NODE_IDS   register.   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 (EUI-64 identifier)         |   +---                            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   |                               |    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).   node_unique_ID  This field contains the node unique ID of the                   node and MUST be equal to that specified in the                   node's configuration ROM.   max_rec         This field MUST be equal to the value of max_rec                   in the node's configuration ROM.   spd             This field MUST be set to the lesser of the node's                   link speed and PHY speed.  The link speed is the                   maximum speed at which the link may send or                   receive packets; the PHY speed is the maximum                   speed at which the PHY may send, receive or repeat                   packets.  The encoding used for spd is specified in                   the Table 2 of [IP1394].Fujisawa & Onoe             Standards Track                     [Page 4]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 2001   unicast_FIFO    This field MUST specify the 48-bit offset of the                   node's FIFO available for the receipt of IPv6                   datagrams.  The offset of a node's unicast FIFO                   MUST NOT change, except as the result of a power                   reset.   reserved        This field MUST be set to all zeros by the sender                   and ignored by the receiver.   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.   According to [1394], the maximum data payload and the transmission   speed SHOULD be determined based on the sender's capability, the   recipient's capability, and the PHYs of all intervening nodes.9. IPv6 MULTICAST   By default, all best-effort IPv6 multicast MUST use asynchronous   stream packets whose channel number is equal to the channel field   from the BROADCAST_CHANNEL register.  In particular, datagrams   addressed to all-nodes multicast addresses, all-routers multicast   addresses, and solicited-node multicast addresses [AARCH] MUST use   the default channel specified by the BROADCAST_CHANNEL register.   Best-effort IPv6 multicast for other 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].   When a node wishes to receive multicast data addressed to other than   all-nodes multicast addresses, all-routers multicast addresses, and   solicited-node multicast addresses, it MUST confirm if the channel   mapping between a multicast group address and a channel number exists   using MCAP, as described in "9.3 Multicast Receive" in [IP1394].   The implementation of MCAP is optional for send-only nodes.  A node   MAY transmit multicast data addressed to any multicast addresses into   the default broadcast channel regardless of the existing allocation   of the channel.  If a node wishes to transmit multicast data on other   than the default channel, it MUST first confirm by MCAP whether or   not a channel number for the group address has been already   allocated.  The implementors are encouraged to use this protocol when   transmitting high-rate multicast streams.   The MCAP 'type' value for IPv6 group address descriptor is 2.Fujisawa & Onoe             Standards Track                     [Page 5]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 200110. IANA CONSIDERATIONS   IANA has assigned a value of 0x000002 for "Unit_SW_Version for IPv6   over IEEE1394" out of the "CSR Protocol Identifiers" name space, as   described insection 5.  The details of the "CSR Protocol   Identifiers" namespace is described in "10. IANA CONSIDERATIONS" of   [IP1394].   Section 9.1 of [IP1394] defines MCAP group address descriptors, which   include an 8-bit type name space.  This document requests that IANA   maintain a name space to manage MCAP group address descriptors.  The   initial assignments for that table are:       Value        Usage       0            reserved       1            IPv4 Multicast Address       2            IPv6 Multicast Address       255          reserved   Additional values from the range 3-254 can be assigned through   Standards Action [RFC 2434].11. Security Considerations   IPv6 over IEEE1394 does not introduce any additional security   considerations over [IP1394].  The security concerns described in   "11. SECURITY CONSIDERATIONS" in [IP1394] apply here as well.12. Acknowledgment   The authors would like to acknowledge the authors of [IP1394] and   [ETHER] since some part of this document has been derived from them.13. References   [1394]   IEEE Std 1394-1995, Standard for a High Performance Serial            Bus   [1394a]  IEEE Std 1394a-2000, Standard for a High Performance Serial            Bus - Amendment 1   [IP1394] Johansson, P., "IPv4 over IEEE 1394",RFC 2734, December            1999.   [IPV6]   Deering, S. and R. Hinden, "Internet Protocol, Version 6            (IPv6) Specification",RFC 2460, December 1998.Fujisawa & Onoe             Standards Track                     [Page 6]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 2001   [AARCH]  Hinden, R. and S. Deering, "IP Version 6 Addressing            Architecture",RFC 2373 December 1998.   [ACONF]  Thomson, S. and T. Narten, "IPv6 Stateless Address            Autoconfiguration",RFC 2462, December 1998.   [DISC]   Narten, T., Nordmark, E., and W. Simpson, "Neighbor            Discovery for IP Version 6 (IPv6)",RFC 2461, December 1998.   [ETHER]  Crawford, M., "Transmission of IPv6 Packets over Ethernet            Networks",RFC 2464, December 1998.14. Authors' Addresses   Kenji Fujisawa   Network & Software Technology Center, Sony Corporation   6-7-35 Kitashinagawa,   Shinagawa-ku, Tokyo 141-0001, JAPAN   Phone: +81-3-5795-8507   Fax:   +81-3-5795-8977   EMail: fujisawa@sm.sony.co.jp   Atsushi Onoe   Internet Systems Laboratory,   Internet Laboratories, Sony Corporation   6-7-35 Kitashinagawa,   Shinagawa-ku, Tokyo 141-0001, JAPAN   Phone: +81-3-5448-4620   Fax:   +81-3-5448-4622   EMail: onoe@sm.sony.co.jpFujisawa & Onoe             Standards Track                     [Page 7]

RFC 3146          IPv6 Packets over IEEE 1394 Networks      October 200115.  Full Copyright Statement   Copyright (C) The Internet Society (2001).  All Rights Reserved.   This document and translations of it may be copied and furnished to   others, and derivative works that comment on or otherwise explain it   or assist in its implementation may be prepared, copied, published   and distributed, in whole or in part, without restriction of any   kind, provided that the above copyright notice and this paragraph are   included on all such copies and derivative works.  However, this   document itself may not be modified in any way, such as by removing   the copyright notice or references to the Internet Society or other   Internet organizations, except as needed for the purpose of   developing Internet standards in which case the procedures for   copyrights defined in the Internet Standards process must be   followed, or as required to translate it into languages other than   English.   The limited permissions granted above are perpetual and will not be   revoked by the Internet Society or its successors or assigns.   This document and the information contained herein is provided on an   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.Acknowledgement   Funding for the RFC Editor function is currently provided by the   Internet Society.Fujisawa & Onoe             Standards Track                     [Page 8]