Basic Forward Error Correction (FEC) Schemes
RFC 5445

Network Working Group                                          M. Watson
Request for Comments: 5445                              Digital Fountain
Obsoletes: 3452, 3695                                         March 2009
Category: Standards Track

              Basic Forward Error Correction (FEC) Schemes

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.

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   document authors.  All rights reserved.

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Abstract

   This document provides Forward Error Correction (FEC) Scheme
   specifications according to the Reliable Multicast Transport (RMT)
   FEC building block for the Compact No-Code FEC Scheme, the Small
   Block, Large Block, and Expandable FEC Scheme, the Small Block
   Systematic FEC Scheme, and the Compact FEC Scheme.  This document
   obsoletes RFC 3695 and assumes responsibility for the FEC Schemes
   defined in RFC 3452.

Watson                      Standards Track                     [Page 1]
RFC 5445                   Basic FEC Schemes                  March 2009

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Requirements Notation  . . . . . . . . . . . . . . . . . . . .  4
   3.  Compact No-Code FEC Scheme . . . . . . . . . . . . . . . . . .  4
     3.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . .  4
     3.2.  Formats and Codes  . . . . . . . . . . . . . . . . . . . .  4
       3.2.1.  FEC Payload ID(s)  . . . . . . . . . . . . . . . . . .  4
       3.2.2.  FEC Object Transmission Information  . . . . . . . . .  5
     3.3.  Procedures . . . . . . . . . . . . . . . . . . . . . . . .  7
     3.4.  FEC Code Specification . . . . . . . . . . . . . . . . . .  7
       3.4.1.  Source Block Logistics . . . . . . . . . . . . . . . .  7
       3.4.2.  Sending and Receiving a Source Block . . . . . . . . .  8
   4.  Small Block, Large Block, and Expandable FEC Scheme  . . . . .  9
     4.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . .  9
     4.2.  Formats and Codes  . . . . . . . . . . . . . . . . . . . .  9
       4.2.1.  FEC Payload ID(s)  . . . . . . . . . . . . . . . . . .  9
       4.2.2.  FEC Object Transmission Information  . . . . . . . . . 10
     4.3.  Procedures . . . . . . . . . . . . . . . . . . . . . . . . 11
     4.4.  FEC Code Specification . . . . . . . . . . . . . . . . . . 12
   5.  Small Block Systematic FEC Scheme  . . . . . . . . . . . . . . 12
     5.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . 12
     5.2.  Formats and Codes  . . . . . . . . . . . . . . . . . . . . 12
       5.2.1.  FEC Payload ID(s)  . . . . . . . . . . . . . . . . . . 12
       5.2.2.  FEC Object Transmission Information  . . . . . . . . . 13
     5.3.  Procedures . . . . . . . . . . . . . . . . . . . . . . . . 14
     5.4.  FEC Code Specification . . . . . . . . . . . . . . . . . . 15
   6.  Compact FEC Scheme . . . . . . . . . . . . . . . . . . . . . . 15
     6.1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . 15
     6.2.  Formats and Codes  . . . . . . . . . . . . . . . . . . . . 15
       6.2.1.  FEC Payload ID(s)  . . . . . . . . . . . . . . . . . . 15
       6.2.2.  FEC Object Transmission Information  . . . . . . . . . 15
     6.3.  Procedures . . . . . . . . . . . . . . . . . . . . . . . . 15
     6.4.  FEC Code Specification . . . . . . . . . . . . . . . . . . 16
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 16
   8.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 16
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 16
   10. Changes from Schemes Defined in RFC 3452 and RFC 3695  . . . . 17
   11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
     11.1. Normative References . . . . . . . . . . . . . . . . . . . 18
     11.2. Informative References . . . . . . . . . . . . . . . . . . 18

Watson                      Standards Track                     [Page 2]
RFC 5445                   Basic FEC Schemes                  March 2009

1.  Introduction