An effective algorithm for delay-constrained dynamic multicasting

With the development of multimedia group applications, the construction of multicast routing tree satisfying Quality of Service (QoS) is more important. In many multicast applications, it is required that the network supports dynamic multicast, which the membership of the multicast group changes with the time. In this paper an effective heuristic algorithm is proposed for dynamic multicast routing with delay-constrained. Aims of this proposed algorithm is to guarantee that: (1) the cost of multicast tree is as small as possible at each node addition/removal event, (2) all the maximal path delay is meet a fixed delay-constrained, (3) minimize perturbation to an existing tree. The proposed algorithm is based on ‘damage’ and ‘usefulness’ concept, and a Balancing Factor (BF) is provided to judge whether or not to arrange a region of tree. Mutation operation in Genetic Algorithm (GA) is also employed to find an attached node in tree for a dynamic adding node. Simulation shows that our algorithm performs well than those static heuristic algorithms in term of cost especially.