SigComp (Signaling Compression)

SigComp (Signaling Compression) is now available starting with the Silver edition.
SigComp stands for Signaling Compression and has been defined in RFC 3320 by the Internet Engineering Task Force (IETF) ROHC working group.

Many application protocols used for multimedia communications are text-based and engineered for bandwidth rich links. As a result the messages have not been optimized in terms of size. For example, typical IMS/SIP messages range from a few hundred bytes up to two thousand bytes or more. For this reason, SigComp is mandatory for 3GPP IMS netwoks and PoC systems.

SigComp could also be useful for RCS (Rich Communication Suite) networks because of the size of the SIP packets (more than three thousand bytes for presence publication). Using SigComp in IMS/RCS context will reduce the round-trip over slow radio links.

Our SigComp implementation has been tested against 3GPP IMS and 3GPP2 MMD networks using [3GPP TS 24.229] and [3GPP2 X.S0013-004-A] compression procedures.

Mercuro IMS Client implements:

• RFC 3320 - Signaling Compression (SigComp)
• RFC 3485 - The Session Initiation Protocol (SIP) and Session Description Protocol (SDP) Static Dictionary for Signaling Compression (SigComp)
• RFC 3486 - Compressing the Session Initiation Protocol (SIP)
• RFC 4077 - A Negative Acknowledgement Mechanism for Signaling Compression
• RFC 4464 - Signaling Compression (SigComp) Users' Guide
• RFC 4465 - Signaling Compression (SigComp) Torture Tests
• RFC 4896 - Signaling Compression (SigComp) Corrections and Clarifications
• RFC 5049 - Applying Signaling Compression (SigComp) to the Session Initiation Protocol (SIP)
• RFC 5112 - The Presence-Specific Static Dictionary for Signaling Compression (Sigcomp)
• 3GPP TR23.979 Annex C - Required SigComp performance
• [3GPP TS 24.229] and [3GPP2 X.S0013-004-A] compression procedures