Internet Engineering Task Force

Robust Header Compression (rohc)

In addition to this official charter maintained by the IETF Secretariat, there is additional information about this working group on the Web at:
Additional ROHC Page

Last Modified: 2007-09-28

Additional information is available at tools.ietf.org/wg/rohc

Chair(s):

Carl Knutsson <carl.knutsson@effnet.com>

Transport Area Director(s):

Transport Area Advisor:

Magnus Westerlund <magnus.westerlund@ericsson.com>

Technical Advisor(s):

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:

Integration of Robust Header Compression over IPsec Security Associations (35956 bytes)
IKEv2 Extensions to Support Robust Header Compression over IPsec (28301 bytes)
IPsec Extensions to Support Robust Header Compression over IPsec (33184 bytes)
The RObust Header Compression (ROHC) Framework (90527 bytes)

Request For Comments: