A heuristic multicast algorithm to support QoS group communications in heterogeneous network

In this paper, we study the problem of QoS group communication in a heterogeneous network, which consists of multiple MANETs attached to the backbone Internet. We propose a heuristic multicast algorithm called DD VMA (delay and delay variation multicast algorithm). DDVMA is designed for solving the DVBMT (delay- and delay variation-bounded multicast tree) problem (G.N. Rouskas and I. Baldine, 1997), which has been proved to be NP-complete. It can find a multicast tree satisfying the multicast end-to-end delay constraint and minimizing the multicast delay variation. Two concepts are introduced: the proprietary second shortest path and partially proprietary second shortest path. These can help DDVMA achieve better performance in terms of the multicast delay variation than DD VCA (delay and delay variation constraint algorithm) (P.R. Sheu and S.T. Chen, 2002) that is known to be the most efficient so far. Theoretical analysis is given to show the correctness of DDVMA and simulations are performed to demonstrate the performance of DD VMA in terms of the multicast delay variation