Effnet CRTP™

The IETF standard for Compressed RTP (RFC 2508) supports compression of RTP/UDP/IP (both IPv4 and IPv6) headers on a per hop basis. This header compression scheme compresses the RTP headers typically down to 2 to 4 bytes. It is designed to work well over low bandwidth links such as dial-up modems.

The IPHC (RFC 2507) can compress UDP traffic which also includes multimedia traffic such as voice over IP and video over IP. Since introduction of RTP to enable interoperability among applications and services, one more protocol header (RTP) has been added. The RTP header of 12 bytes is a large overhead for a payload of typically 20 bytes. The header compression scheme CRTP fulfils the need to compress away that overhead and reduce bandwidth consumption even more.

The IETF has been developing the CRTP standard further with new standards like Enhanced CRTP (RFC 3545) for links with high delay, packet loss and reordering and a draft version of Tunnelling multiplexed Compressed RTP (TCRTP) is now available. Effnet's research and development team is actively involved in the standardization process including further development of the standard.

General features

• Software fully compliant with the IETF standard RFC 2508
• Lightweight implementation including all features suitable for low-end devices
• Highly portable ANSI C code with no operating system dependencies
• Platform, endianness and byte-order independent
• Highly configurable with compile and run-time options
• Multi-threading support
• Extensively tested, in-house as well as during interoperability and field tests

Effnet CRTP™ v.3.2 or “Effnet ECRTP™ v.1.0”

This release comes with an optional added support for ECRTP, Enhanced Compressed RTP (IETF RFC 3545). This version of Effnet CRTP™ can operate either as pure CRTP (RFC 2508) or with all the extended functionality from the RFC 3545. All configuration parameters according to RFC 3544 are supported.

With the modifications and extensions that come with ECRTP, Effnet CRTP™ v.3.2 will enable the use of header compression over IP tunnels and other virtual circuits, where packet losses, reordering and long delays are common characteristics.

Effnet CRTP™ v.3.1

The new release of Effnet CRTP™ v.3.1, is now based on the Effnet standard framework used for portability and debugging. The new release includes:

• Improved standards conformity which has been interop tested
• Optimized compression
• Sample code which makes usage and intergration easier
• Optional advanced simulation enviroment, Effnet HC-Sim™