Admission Control for Multicast Routing with Quality of Service in Ad Hoc Networks

Ad hoc networks, being able to organize themselves without user intervention, can easily provide their users with mobility, multimedia support and group communication. However, they have to combine quality of service (QoS) and multicast routing strategies. This article defines the resource management and admission control components of the ad hoc QoS multicast (AQM) routing protocol, which achieves multicast efficiency along the network. When nodes wish to join a session, a request-reply-reserve process ensures that an appropriate QoS route is selected. Nodes are prevented from applying for membership if there is no QoS path for the session. To cope with the continuous nature of multimedia, AQM nodes check the availability of bandwidth in a virtual tunnel of nodes. Objection queries are issued prior to admission in order to avoid excessive resource usage by the nodes which cannot detect each other. New performance metrics are introduced to evaluate AQM’s member and session satisfaction rates. Simulation results show that AQM improves multicast efficiency both for members and sessions.