Simplified Multicast Forwarding
RFC 6621

Internet Engineering Task Force (IETF)                    J. Macker, Ed.
Request for Comments: 6621                                           NRL
Category: Experimental                                          May 2012
ISSN: 2070-1721

                    Simplified Multicast Forwarding

Abstract

   This document describes a Simplified Multicast Forwarding (SMF)
   mechanism that provides basic Internet Protocol (IP) multicast
   forwarding suitable for limited wireless mesh and mobile ad hoc
   network (MANET) use.  It is mainly applicable in situations where
   efficient flooding represents an acceptable engineering design trade-
   off.  It defines techniques for multicast duplicate packet detection
   (DPD), to be applied in the forwarding process, for both IPv4 and
   IPv6 protocol use.  This document also specifies optional mechanisms
   for using reduced relay sets to achieve more efficient multicast data
   distribution within a mesh topology as compared to Classic Flooding.
   Interactions with other protocols, such as use of information
   provided by concurrently running unicast routing protocols or
   interaction with other multicast protocols, as well as multiple
   deployment approaches are also described.  Distributed algorithms for
   selecting reduced relay sets and related discussion are provided in
   the appendices.  Basic issues relating to the operation of multicast
   MANET border routers are discussed, but ongoing work remains in this
   area and is beyond the scope of this document.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for examination, experimental implementation, and
   evaluation.

   This document defines an Experimental Protocol for the Internet
   community.  This document is a product of the Internet Engineering
   Task Force (IETF).  It represents the consensus of the IETF
   community.  It has received public review and has been approved for
   publication by the Internet Engineering Steering Group (IESG).  Not
   all documents approved by the IESG are a candidate for any level of
   Internet Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6621.

Macker                        Experimental                      [Page 1]
RFC 6621                           SMF                          May 2012

Copyright Notice

   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   than English.

Table of Contents

   1. Introduction and Scope ..........................................4
   2. Terminology .....................................................4
   3. Applicability Statement .........................................5
   4. Overview and Functioning ........................................6
   5. SMF Packet Processing and Forwarding ............................8
   6. SMF Duplicate Packet Detection .................................10
      6.1. IPv6 Duplicate Packet Detection ...........................11
           6.1.1. IPv6 SMF_DPD Option Header .........................12
           6.1.2. IPv6 Identification-Based DPD ......................14
           6.1.3. IPv6 Hash-Based DPD ................................16
      6.2. IPv4 Duplicate Packet Detection ...........................17
           6.2.1. IPv4 Identification-Based DPD ......................18
           6.2.2. IPv4 Hash-Based DPD ................................19