RFC 3228

RFC 3228 🎀 IANA Considerations for IPv4 Internet Group Management Protocol (IGMP)

okay bestie, the title block is giving paperwork but here's the tea 🫶 This is RFC 3228, written by B. Fenner from AT&T Research, dated February 2002. It's a Best Current Practice (BCP 57 💅), so it's a community guideline rather than a protocol spec. The header doesn't list anything it obsoletes or updates. Lowkey iconic for a document about registries 📋

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Status of This Memo ✨

so this doc is an Internet Best Current Practice for the Internet Community, and it's asking everyone for discussion and suggestions for improvements 🦋 Distribution of this memo is unlimited, so share it with everyone 💜

Copyright Notice 🌈

Copyright (C) The Internet Society (2002). All Rights Reserved. The full legal wording is in the last section, so skip ahead if you want the fine print 🙈

Abstract 🌸

this memo asks IANA to make a registry for the fields in the IGMP (Internet Group Management Protocol) header, and gives IANA guidance on how to assign values for those fields 🧚

Table of Contents 📖

1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . .   1
2. IANA Considerations for fields in the IPv4 IGMP header. . . .   2
3. Assignments for testing and experimentation . . . . . . . . .   2
4. Security Considerations . . . . . . . . . . . . . . . . . . .   2
5. Normative References. . . . . . . . . . . . . . . . . . . . .   2
6. Informative References. . . . . . . . . . . . . . . . . . . .   3
7. Author's Address. . . . . . . . . . . . . . . . . . . . . . .   3
8. Full Copyright Statement. . . . . . . . . . . . . . . . . . .   4

1. Introduction 💖

this memo asks IANA to create a registry for the fields in the IGMP protocol header 🍓

bestie, notice the words "Specification Required", "Expert Review", "IESG Approval", "IETF Consensus", and "Standards Action". The memo uses them to point at the processes described in [2] 🔥

2. IANA Considerations for fields in the IPv4 IGMP header 👑

the IPv4 IGMP header [1] has two fields that carry values from IANA-managed name spaces: Type and Code. The Code field values are defined relative to a specific Type value 🫶

the Type values get allocated using an IESG Approval or Standards Action process. Code values for existing IPv4 IGMP Type fields also get allocated through IESG Approval or Standards Action processes ✨

for new IPv4 IGMP Types, the policy for assigning Code values should be defined in the document that defines the new Type value 💅

3. Assignments for testing and experimentation 🧪

instead of suggesting temporary assignments the way [3] does, this doc follows the lead of [4] and reserves a range of values for experimental use. The IGMP Code values 240-255 inclusive (0xf0 - 0xff) are reserved for protocol testing and experimentation 🦋

systems should silently ignore IGMP messages with unknown Code values 🙈

4. Security Considerations 🔐

this section is serious, bestie, so read it twice 💀

security analyzers like firewalls and network intrusion detection monitors often depend on unambiguous readings of the fields in this memo 😭 When new field values get assigned, analyzers that don't understand them might fail. That can cause a loss of connectivity if the analyzer refuses to forward the unrecognized traffic. It can also cause a loss of security if the analyzer does forward it and the new values are used as part of an attack 🚨

so this is why high visibility matters, and why the Standards Action and IETF Consensus processes are the way to go whenever possible 🌸

5. Normative References 📚

• [1] Fenner, W., "Internet Group Management Protocol, Version 2", RFC 2236, November 1997.
• [2] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998.

6. Informative References 🧚

• [3] Bradner, S. and V. Paxson, "IANA Allocation Guidelines For Values In the Internet Protocol and Related Headers", BCP 37, RFC 2780, March 2000.
• [4] Narten, T., "Assigning Experimental and Testing Numbers Considered Useful", Work in Progress.

7. Author's Address 🎀

Bill Fenner
AT&T Labs -- Research
75 Willow Rd
Menlo Park, CA 94025
USA

EMail: fenner@research.att.com

8. Full Copyright Statement 💜

the legal text is kept word for word below, because it has to be 🫶

Copyright (C) The Internet Society (2002).  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
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TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
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Acknowledgement 🌈

funding for the RFC Editor function is currently provided by the Internet Society ✨