Research of multi-constrained multicast routing Qos using heuristic algorithm

Multicast is widely applied for multimedia communications in Internet. The effective multicast routing is the key technology to the communications. The Qos of multi-constrained multicast routing problem deserves more attention. The objective function is to minimize the cost and meet multiple constraints to realize high Qos. The solutions' fitness is obtained by the concentration mechanism of immune algorithm and the affinity is helpful to the probability update strategy. The node linkage which belongs to the excellent solution has greater probability to be chosen. During the evolutionary process of the algorithm the constraint equation is dynamic adjusted to avoid unnecessary search and shorten the search time. Each invalid path is recorded into the Tabu table as a constraint to guide the next iteration. The heuristic Immune-PBIL algorithm is tested on a network topology and some multicast routing demand is considered. The result also shows that the advanced evolutionary strategies according to the Qos are high efficient and the global search capability is improved.