Narrow Results

The purpose of this paper is to evaluate the performance of H.323 handoff methods that use ad hoc multipoint conference, transfer, and third party rerouting signaling respectively. This performance is evaluated in terms of inter-operability and signaling delay. The inter-operability specification includes multipoint conference messages, H.450.2 messages, and null TerminalCapabilitySet message. The delay of each signaling is analyzed into number of TCP connections and number of logical channel setup procedures. The results of our experiment show that third party rerouting signaling has better result than other signalings in inter-operating with terminals of four vendors, since it uses only H.323 mandatory messages. Also it requires fewer number of TCP connections and logical channel setup procedures than the others do, so it can reduce the signaling delay by 1.4 sec in average.