Skip to main content

IP Multicast Requirements for a Network Address Translator (NAT) and a Network Address Port Translator (NAPT)

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: Internet Architecture Board <>,
    RFC Editor <>, 
    behave mailing list <>, 
    behave chair <>
Subject: Protocol Action: 'IP Multicast Requirements for a 
         Network Address (and port) Translator (NAT)' to BCP 

The IESG has approved the following document:

- 'IP Multicast Requirements for a Network Address (and port) Translator 
   (NAT) '
   <draft-ietf-behave-multicast-13.txt> as a BCP

This document is the product of the Behavior Engineering for Hindrance 
Avoidance Working Group. 

The IESG contact persons are Magnus Westerlund and Lars Eggert.

A URL of this Internet-Draft is:

Ballot Text

Technical Summary

   In order for IP multicast applications to function well over NATs,
   multicast UDP must work as seamlessly as unicast UDP.  However, NATs
   have little consistency in IP multicast operation which results in
   inconsistent user experiences and failed IP multicast operation.

   This document targets requirements intended to enable correct
   operations of Any Source Multicast and Source-Specific Multicast in
   devices running IGMP proxy routing and NAT and without applying NAT
   to IP multicast group addresses.  This profile of functionality is
   the expected best practice for residential access routers small
   branch routers or similar deployments.
Working Group Summary

   There was a consensus in the WG to publish this document. 
Document Quality

   This document was reviewed by both BEHAVE WG participants as well as 
   participants from the MAGMA WG. This has resulted in a well reviewed 
   document that addresses both the multicast and NAT aspects very well.
   This document was shepherd by the responsible AD Magnus Westerlund due
   to the author being WG chair.

RFC Editor Note