datatracker.ietf.org
Sign in
Version 5.12.0, 2015-02-26
Report a bug

RObust Header Compression (ROHC): Profiles for User Datagram Protocol (UDP) Lite
RFC 4019

Document type: RFC - Proposed Standard (April 2005; No errata)
Updated by RFC 4815
Document stream: IETF
Last updated: 2013-03-02
Other versions: plain text, pdf, html

IETF State: (None)
Consensus: Unknown
Document shepherd: No shepherd assigned

IESG State: RFC 4019 (Proposed Standard)
Responsible AD: Allison Mankin
Send notices to: cabo@tzi.org, lars-erik.jonsson@ericsson.com

Network Working Group                                       G. Pelletier
Request for Comments: 4019                                   Ericsson AB
Category: Standards Track                                     April 2005

                   RObust Header Compression (ROHC):
             Profiles for User Datagram Protocol (UDP) Lite

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

   Copyright (C) The Internet Society (2005).

Abstract

   This document defines Robust Header Compression (ROHC) profiles for
   compression of Real-Time Transport Protocol, User Datagram Protocol-
   Lite, and Internet Protocol (RTP/UDP-Lite/IP) packets and UDP-
   Lite/IP.  These profiles are defined based on their differences with
   the profiles for UDP as specified in RFC 3095.

Table of Contents

   1.  Introduction..................................................  2
   2.  Terminology...................................................  3
   3.  Background....................................................  3
       3.1.  Overview of the UDP-Lite Protocol.......................  3
       3.2.  Expected Behaviours of UDP-Lite Flows...................  5
             3.2.1.  Per-Packet Behavior.............................  5
             3.2.2.  Inter-Packet Behavior...........................  5
             3.2.3.  Per-Flow Behavior...............................  5
       3.3.  Header Field Classification.............................  5
   4.  Rationale behind the Design of ROHC Profiles for UDP-Lite.....  6
       4.1.  Design Motivations......................................  6
       4.2.  ROHC Considerations.....................................  6
   5.  ROHC Profiles for UDP-Lite....................................  6
       5.1.  Context Parameters......................................  7
       5.2.  Initialization..........................................  8
             5.2.1.  Initialization of the UDP-Lite Header [1].......  8
             5.2.2.  Compressor and Decompressor Logic...............  9

Pelletier                   Standards Track                     [Page 1]
RFC 4019              ROHC: Profiles for UDP-Lite             April 2005

       5.3.  Packet Formats..........................................  9
             5.3.1.  General Packet Format...........................  9
             5.3.2.  Packet Type CCE: CCE(), CCE(ON), and CCE(OFF)... 10
                     5.3.2.1.  Properties of CCE():.................. 11
                     5.3.2.2.  Properties of CCE(ON):................ 11
                     5.3.2.3.  Properties of CCE(OFF):............... 12
       5.4.  Compressor Logic........................................ 12
       5.5.  Decompressor Logic...................................... 12
       5.6.  Additional Mode Transition Logic........................ 13
       5.7.  The CONTEXT_MEMORY Feedback Option...................... 13
       5.8.  Constant IP-ID.......................................... 13
   6.  Security Considerations....................................... 14
   7.  IANA Considerations........................................... 14
   8.  Acknowledgments............................................... 15
   9.  References.................................................... 15
       9.1.  Normative References.................................... 15
       9.2.  Informative References.................................. 15
   Appendix A.  Detailed Classification of Header Fields............. 17
   Appendix B.  Detailed Format of the CCE Packet Type............... 20
   Author's Address.................................................. 22
   Full Copyright Statement.......................................... 23

1.  Introduction

   The ROHC WG has developed a header compression framework on top of
   which various profiles can be defined for different protocol sets or
   compression strategies.  Due to the demands of the cellular industry
   for an efficient way to transport voice over IP over wireless, ROHC
   [2] has mainly focused on compression of IP/UDP/RTP headers, which
   are generous in size, especially compared to the payloads often
   carried by packets with these headers.

   ROHC RTP has become a very efficient, robust, and capable compression
   scheme, able to compress the headers down to a total size of one
   octet only.  Also, transparency is guaranteed to an extremely high
   extent, even when residual bit errors are present in compressed

[include full document text]