In this paper, we provide a detailed description of an algorithm that implements join and prune mechanisms, which will help to build an optimal multicast tree with QoS requirements during handoff. An analysis is presented to show how mobility prediction can help in the selection of potential access routers (AR) with QoS requirements that affect multicast group size and bandwidth cost in the multicast tree. The proposed technique tries to minimise the number of multicast tree join and prune operations. We have examined the performance of this algorithm using simulations in various environments and obtained good performance results. Our results show that the expected multicast group increases linearly with the increase in the number of selected destination access routers (AR) for multicast during handoff. We observe that the expected number of joins and prunes from the multicast tree increases with group size. Thus, for an increased number of destinations, the estimated cost of the multicast tree in a cellular network also increases
