The Research And Simulation On Mobile Ad Hoc Network Tree Multicast Routing Optimization

Mobile Ad hoc Network (MANET) as a new communications network,Includes many new technologies and new problems,so majority of scientists are very concerned about it. Its many features open up broad prospects for its application. This paper focuses on the MANET multicast routing protocols.Multicast Routing corresponding to the Steiner tree problem of Graph. Steiner tree algorithm for solving the multicast session in accordance with the process of the relationship between group member nodes are divided into static and dynamic two algorithms; In accordance with the conditions , we also can divided multicast routing algorithms into "best effort" Multicast routing and QoS multicast routing. To analysis and verification the study conclusion , the thesis selected NS-2 simulation tool, and discussed NS-2's structure, components, and process of simulation. Finally, the author solved two problems based on Steiner tree algorithm and related theory : First, based on the idea of dynamic partial rearrangeable algorithm on Steiner tree. author improved MAODV. The new algorithm named DPRMR. Focusing on the process of the overall cost of the multicast tree when the node of multicast group members leave the tree. the author creative use of "event trigger" concept, effective solution the problem of reconstruction algorithm trigger threshold difficult to control, Used the simulation software (NS-2), compared and analysed between MAODV and DPRMR. The results showed that DPRMR algorithm in a slight increase in overhead, improved the network end-to-end delay and packet delivery ratio .Second, the Steiner Tree problem in accordance with the unconstrained and constrained classification, author careful study, including Prim, KMB, Dijkstra and KPP, BSMA, QDMR, etc., the classical algorithm. additional MANET network bandwidth and delay estimation algorithm , Limit the number of control packets by flooding algorithm, and designed select function .Sproposes a heuristic QoS Multicast Routing Protocol named BDCMR. Route discovery process of the algorithm can satisfy bandwidth and delay constraints, and the success rate in routing while ensuring effective in reducing the control overhead .