The Optimization Of Mobile Multicast Protocol Based On Agent

Mobile communication is playing an increasing role in our lives. Mobile users expect similar kinds of applications to static ones, the most important is to resolve mobile handoff and the restriction of wireless bandwidth. Multicast not only brings attractive applications, but also has the benefit of saving scarce bandwidth in wireless environment. It would be fruitful to combine these two technologies.In this paper, we research and compare some mobile multicast protocols and present a new mechanism based on Agent to reduce handoff latency for mobile multicast. The Agent acts as a proxy for the Internet Group Management Protocol (IGMP) of mobile nodes and keeps information for members of multicast groups in a cell. When a mobile node moves to other cell, the Agent immediately sends unsolicited reports without waiting for the IGMP query. In addition, our mechanism may conserve battery power since it does not need to reply to a query. The mechanism is evaluated through simulation and compared with the IGMPv2 for mobility and IGMP traffic. Simulation results show that handoff latency and the lost of packets can be largely reduced, also the IGMP control traffic can be eliminated on the wireless links.