RFC 3146

Transmission of IPv6 Packets over IEEE 1394 Networks

📅 published October 2001, from ietf

RFC 3146: Transmission of IPv6 Packets over IEEE 1394 Networks 🎀

okay bestie, the title block is giving 🧚 This is RFC 3146 from the Network Working Group. The authors are K. Fujisawa and A. Onoe, both at Sony Corporation. It's a Standards Track doc, dated October 2001. The title block doesn't list anything it obsoletes or updates. 💖

Status 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 💅

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 ✨

okay so IEEE Std 1394-1995 (and its amendment) is a standard for a High Performance Serial Bus 🔥 The IETF IP1394 Working Group already standardized how to carry IPv4 datagrams and ARP packets over an IEEE1394 subnetwork [IP1394]. Iconic.

This document is the next step. It describes the frame format for transmission of IPv6 [IPV6] packets, plus how to form IPv6 link-local addresses and statelessly autoconfigured addresses on IEEE1394 networks. It also covers the content of the Source/Target Link-layer Address option used in Neighbor Discovery [DISC] when those messages are sent over an IEEE1394 network. Main character energy 🦋

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 read as described in RFC 2119. no cap, these words are doing a lot of work here 🫶

3. IPv6-CAPABLE NODES 🧚

An IPv6-capable node MUST meet these minimum requirements, bestie:

it MUST implement configuration ROM in the general format specified by ISO/IEC 13213:1994, and it 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 means it can accept block write requests and asynchronous stream packets with a data payload of 512 octets. The same ability MUST also apply to read requests. In other words, 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]. Same vibes, same rules 💖

Note: Since there is an ether_type field to tell protocols apart, and MCAP (multicast channel allocation protocol) is used for both IPv4 and IPv6, the version field in the GASP (global asynchronous stream packet) header of IPv6 datagrams has the same value (one) as in [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 that 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. ngl that's a very specific rule and I respect it 💅

The mechanism to extend MTU size between two particular nodes is for further study. 🔮

5. CONFIGURATION ROM 🌈

Configuration ROM for IPv6-capable nodes MUST contain a unit directory in the format specified by [IP1394], except for the 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, one for IPv4 and one for IPv6 respectively. two directories, one for each stack, very organized 🗂️

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. That's the next-to-lowest order bit of the first octet of the EUI-64 identifier. Complementing this bit will usually change a 0 into a 1, because an interface's built-in EUI-64 identifier is expected to come from a universally administered address space and so have a globally unique value. A universally administered EUI-64 identifier has a 0 in the U/L bit position, while a globally unique IPv6 Interface Identifier has a 1 in that same spot. For more on this, 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. Here's the layout:

  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 Neighbor Discovery [DISC]. The 1394 link address (node_ID) won't stay constant across a 1394 bridge, so the spec chose not to put it in the Link-layer Address option. The recipient of the Neighbor Discovery message SHOULD use the source_ID (obtained from either the asynchronous packet header or the GASP header) together with the content of the Source link-layer address. An implementation MAY use some other method to obtain the node_ID of the sender, using a mapping table between node_unique_ID (EUI-64 identifier) and node_ID. How to build that mapping table is out of scope for this document. 🙈

The recipient of a 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                           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Here's what each field means:

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].

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 a 1394 bus-reset occurs. The mapping cache held in the node SHOULD be cleared on a 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. Specifically, 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 use a different channel number, but only if that channel number is allocated and advertised before use by the multicast channel allocation protocol (MCAP), as described in [IP1394].

When a node wants to receive multicast data addressed to anything other than all-nodes multicast addresses, all-routers multicast addresses, and solicited-node multicast addresses, it MUST confirm whether 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 wants to transmit multicast data on a channel other than the default, it MUST first confirm through MCAP whether a channel number for the group address has already been allocated. The implementors are encouraged to use this protocol when transmitting high-rate multicast streams. 🚀

The MCAP 'type' value for the IPv6 group address descriptor is 2.

10. 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 in section 5. The details of the "CSR Protocol Identifiers" namespace are 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].

part 1 of 2 done, bestie 🧚 part 2 is coming with the rest of the doc, so stay tuned 💖

11. Security Considerations 🔐

okay so the security part is actually short and sweet bestie 🫶 IPv6 over IEEE1394 doesn't add any extra security considerations on top of [IP1394]. The security concerns described in "11. SECURITY CONSIDERATIONS" in [IP1394] apply here as well. so go read that section if you want the full tea ☕💅

12. Acknowledgment 🎀

the authors gave a shoutout to the people who wrote [IP1394] and [ETHER] 🙌 because parts of this doc were borrowed (in the nicest way) 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.

[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 💌

these are the lovely people who wrote it 🧚

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.jp

15. Full Copyright Statement ⚖️

the legal part, kept word-for-word so nothing gets lost in translation 🙏

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 💜 and that's a wrap, periodt ✨

📦 where this page comes from

ietf: rfc3146 2001-10
💖 girlified by claude-haiku-5-5 on 2026-10-16: a language model's rewrite of the original, under its terms