Robust Header Compression (rohc) -------------------------------- Charter Last Modified: 2007-09-28 Current Status: Active Working Group Chair(s): Carl Knutsson Transport Area Director(s): Magnus Westerlund Lars Eggert Transport Area Advisor: Magnus Westerlund Technical Advisor(s): Erik Nordmark Carsten Bormann Mailing Lists: General Discussion:rohc@ietf.org To Subscribe: rohc-request@ietf.org Archive: http://www.ietf.org/mail-archive/web/rohc/index.html Description of Working Group: The Robust Header Compression (ROHC) Working Group was formed to develop new header compression protocols, designed to suit today's and future target link technologies. Most specifically, the ROHC protocols were to take into account typical needs presented by various wireless link technologies, and perform well for cellular links built using technologies such as WCDMA, EDGE, and CDMA-2000. Protocol development has thus focused on coping with issues such as high loss rates and long round trip times. The WG has specified a common compression protocol platform, the ROHC framework, along with a number of compression protocols (profiles). Most focus has been on compression of the Real-time Transport Protocol (RTP) headers, but profiles have also been specified for compression of UDP, ESP, IP-only, UDP-Lite, and TCP headers. The WG has further produced a ROHC link integration specification for PPP, an optimized RTP compression scheme for "0-byte compression", a ROHC MIB, as well as various informational documents related to ROHC header compression and/or header compression in general. In addition to the work on header compression, the ROHC WG has also developed the SigComp (Signaling Compression) protocol for end-to-end compression of text-based signaling protocol messages. The working group maintains connections with other standardization organizations developing cellular technology for IP, such as 3GPP and 3GPP-2, to ensure that its output fulfills their requirements and will be put to good use. The current aims of the working group are: - to carry out a re-work of the ROHC framework and profiles specifications, hereafter referred to as the ROHCv2 project. The purpose of the ROHCv2 project is to generate a separate framework specification, not changing the framework part of the ROHC protocol, as well as a set of revised compression profiles. The most specific goals with the ROHCv2 profiles are to improve tolerance to packet reordering between compressor and decompressor, and to reduce the overall complexity of the protocol. It should be noted that the v2 profiles will thus not be compatible with the original (ROHCv1) profiles, which means less complex ROHC implementations can be realized by not providing support for ROHCv1 (over links not yet supporting ROHC, or by shifting out support for ROHCv1 in the long run). Profile support is agreed through the ROHC channel negotiation, which is part of the ROHC framework and thus not changed by ROHCv2. - to update and correct the original profile specifications through publication of the "Corrections and Clarifications to RFC 3095"- document. - to finalize the ROHC profile work for TCP header compression. - to develop and/or document proper protocol solutions to apply ROHC over IPsec tunnels. - to finalize the "SigComp implementer's guide" and "SigComp for SIP" documents. The longer term goal of the working group is to advance all its specifications to Draft Standard status (with an exception for the original profiles being revised as part of the ROHCv2 activity). Goals and Milestones: Done Submit I-D on Requirements for IP/UDP/RTP header compression. Done Submit I-D of layer-2 design guidelines. Done Submit I-D(s) proposing IP/UDP/RTP header compression schemes. Done Submit I-D of Requirements for IP/TCP header compression. Done Requirements for IP/UDP/RTP header compression submitted to IESG for publication as Informational. Done Resolve possibly multiple IP/UDP/RTP compression schemes into a single scheme. Done Submit I-D on IP/TCP header compression scheme. Done IP/UDP/RTP header compression scheme submitted to IESG for publication as Proposed Standard. Done Layer-2 design guidelines submitted to IESG for publication as Informational. Done Initial draft on general signaling compression security analysis. Done Requirements and assumptions for signaling compression Done Signaling compression scheme submitted to IESG for publication as Proposed Standard, including security approach for SIP compression usage. Done General signaling compression security analysis submitted to IESG for publication as Informational. Done ROHC MIB submitted to IESG for publication as Proposed Standard. Done ROHC IP-only profile submitted to IESG for publication as Proposed Standard Done ROHC UDP Lite schemes submitted to IESG for publication as Proposed Standard. Done Requirements for IP/TCP header compression submitted to IESG for publication as Informational. Done Problem analysis ROHC-over-channels-that-can-reorder-packets submitted to IESG for publication as Informational Done I-Ds of ROHC IP/UDP/RTP bis, framework and profiles separated. Done RFC 3095 Implementer's Guide submitted to IESG for publication as Proposed Standard Done IP/TCP compression scheme submitted to IESG for publication as Proposed Standard Done ROHC framework submitted to IESG for publication as Proposed Standard Done SigComp for SIP submitted to IESG for publication as Proposed Standard Dec 2006 Revised ROHC IP/UDP/RTP profiles submitted to IESG for publication as Proposed Standard Done SigComp Implementer's Guide submitted to IESG for publication as Proposed Standard Jan 2007 RObust Header Compression Protocol Number Registration submitted to IESG for publication as Proposed Standard Feb 2007 ROHC encapsulation profile(s) for IPHC/CRTP/eCRTP submitted to IESG for publication as Proposed Standard Mar 2007 IKE/IPsec extensions for HC-session Parameter Negotiation submitted to IESG for publication as Proposed Standard Mar 2007 Header Compression over IPsec (HCoIPsec) submitted to IESG for publication as Informational Jun 2007 Recharter of WG to develop additional profiles if needed, or possible additional compression schemes. Consideration of concluding the working group. Internet-Drafts: Posted Revised I-D Title ------ ------- -------------------------------------------- Nov 2005 Jan 2008 Integration of Robust Header Compression (RoHC) over IPsec Security Associations Sep 2006 Jan 2008 RObust Header Compression Version 2 (ROHCv2): Profiles for RTP, UDP, IP, ESP and UDP Lite Sep 2006 Jan 2008 IKEv2 Extensions to Support Robust Header Compression over IPsec (RoHCoIPsec) Aug 2007 Jan 2008 IPsec Extensions to Support Robust Header Compression over IPsec (RoHCoIPsec) Request For Comments: RFC Stat Published Title ------- -- ----------- ------------------------------------ RFC3095 PS Jul 2001 RObust Header Compression (ROHC) RFC3096 I Jul 2001 Requirements for robust IP/UDP/RTP header compression RFC3242 PS May 2002 A Link-Layer Assisted ROHC Profile for IP/UDP/RTP RFC3243 I May 2002 Requirements and assumptions for ROHC 0-byte IP/UDP/RTP compression RFC3241 PS May 2002 ROHC over PPP RFC3408 PS Dec 2002 Zero-byte Support for Reliable Bidirectional Mode (R-mode) in Extended Link-Layer Assisted RObust Header Compression (ROHC) Profile RFC3409 I Dec 2002 Lower Layer Guidelines for Robust RTP/UDP/IP Header Compression RFC3321 I Jan 2003 SigComp - Extended Operations RFC3320 PS Jan 2003 Signaling Compression RFC3322 I Jan 2003 Signaling Compression Requirements & Assumptions RFC3759 I Apr 2004 RObust Header Compression (ROHC):Terminology and Channel Mapping Examples RFC3816Standard Jun 2004 Definitions of Managed Objects for Robus Header Compression RFC3843Standard Jul 2004 RObust Header Compression (ROHC): A Compression Profile for IP RFC4019Standard Apr 2005 RObust Header Compression (ROHC):Profiles for UDP-Lite RFC4077Standard May 2005 A Negative Acknowledgement Mechanism for Signaling Compression RFC4163 I Aug 2005 RObust Header Compression (ROHC): Requirements on TCP/IP Header Compression RFC4164Standard Sep 2005 RObust Header Compression (ROHC):Context Replication for ROHC Profiles RFC4224 I Jan 2006 RObust Header Compression (ROHC): ROHC over Channels that can Reorder Packets RFC4362Standard Jan 2006 RObust Header Compression (ROHC): A Link-Layer Assisted Profile for IP/UDP/RTP RFC4413 I Mar 2006 TCP/IP Field Behavior RFC4464 I May 2006 Signaling Compression (SigComp) Users' Guide RFC4465 I Jun 2006 Signaling Compression (SigComp) Torture Tests RFC4815 PS Feb 2007 RObust Header Compression (ROHC): Corrections and Clarifications to RFC 3095 RFC4896 PS Jun 2007 Signaling Compression (SigComp) Corrections and Clarifications RFC4997 PS Jul 2007 Formal Notation for RObust Header Compression (ROHC-FN) RFC4996 PS Jul 2007 RObust Header Compression (ROHC): A Profile for TCP/IP (ROHC-TCP) RFC4995 PS Jul 2007 The RObust Header Compression (ROHC) Framework RFC5049 PS Dec 2007 Applying Signaling Compression (SigComp) to the Session Initiation Protocol (SIP)