Comparison of Call Signalling Protocols for Ad-hoc Networks

The two major standards in the multimedia services over IP area are the protocol suites H.323 (ITU-T) and SIP (IETF).Both have emerged as competing protocol standards for the signaling and call control of IP telephony. SIP is designed with a broader scope, offering functions specifically designed to enable easy extensions; it should be the advantage for new potential services. H.323 is still the more mature standard; H.323 provides better interoperability and interworking (PSTN, ISDN). We can assume a coexistence of both protocols. We compare voice performance parameters like talking time, total sessions, delay, jitter packet delivery ratio, call set up times and throughput, establish the differences in performance of these two VoIP protocols through an Qualnet simulation. SIP and H.323 are used for establishment and release of Voice over IP calls as well as Video and Media calls. Both these protocols play a very important role in terms of optimizing the call set up time and call reliability and flexibility over IP networks for real time applications like voice and video. The obtained results are discussed to highlight the impact of both H.323 and SIP in adhoc networks.