RFC 3242 (rfc3242) - Page 1 of 21
RObust Header Compression (ROHC): A Link-Layer Assisted Profile for IP/UDP/RTP
Alternative Format: Original Text Document
Network Working Group L-E. Jonsson
Request for Comments: 3242 G. Pelletier
Category: Standards Track Ericsson
April 2002
RObust Header Compression (ROHC):
A Link-Layer Assisted Profile for IP/UDP/RTP
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 (2002). All Rights Reserved.
Abstract
This document defines a ROHC (Robust Header Compression) profile for
compression of IP/UDP/RTP (Internet Protocol/User Datagram
Protocol/Real-Time Transport Protocol) packets, utilizing
functionality provided by the lower layers to increase compression
efficiency by completely eliminating the header for most packets
during optimal operation. The profile is built as an extension to
the ROHC RTP profile. It defines additional mechanisms needed in
ROHC, states requirements on the assisting layer to guarantee
transparency, and specifies general logic for compression and
decompression making use of this header-free packet.
Table of Contents
1. Introduction....................................................2
2. Terminology.....................................................4
3. Overview of the Link-Layer Assisted Profile.....................5
3.1. Providing Packet Type Identification.....................6
3.2. Replacing the Sequence Number............................6
3.3. CRC Replacement..........................................7
3.4. Applicability of This Profile............................7
4. Additions and Exceptions Compared to ROHC RTP...................8
4.1. Additional Packet Types..................................8
4.1.1. No-Header Packet (NHP)..........................8
4.1.2. Context Synchronization Packet (CSP)............8
4.1.3. Context Check Packet (CCP)......................9
Jonsson, et. al Standards Track