Performance enhancement of signaling compression in IP Multimedia Subsystem

In this paper, multiple compression algorithms have been compared and in accordance with the characteristics of the session initiation protocol (SIP), empel-ziv-storer-szymanski (LZSS) is selected as the basic algorithm for the SIP signaling compression (SigComp) in IP multimedia subsystem (IMS). In order to further enhance the SIP SigComp ratio, the LZSS with Huffman coding compression algorithm as well as the detailed implementation procedure is proposed in this paper. With the aid of Huffman coding, a shorter code is utilized to indicate high probability symbol in SIP message and a longer code for the symbol with low probability. And hence, the average code length can be reduced and the message compression ratio can be enhanced. Simulation results showed that with proposed algorithm the message compression ratio can be greatly reduced which results into a reduction of session delay.