Research on Latency of Vertical Handoff Using MSCTP and MSIP

To provide users with real-time service under ubiquitous, heterogeneous wireless access network environment, latency of vertical handoff should be reduced. This paper did a research on UMTS/WALN vertical handoff based on MSCTP(Mobile SCTP) and MSIP(Mobile SIP), analyzed the latency caused by wireless transmission of handoff control signal. The analysis proved that the wireless transmission delay have a great influence on handoff latency. At last a improved vertical handoff scheme had been put forward to get better performance by reducing the wireless transmission delay. The improved scheme had been verified to have less latency than other schemes only based on MSCTP or MSIP and could meet the needs of real-time service by simulations of wireless transmission delay.