Research On Multicast Routing Algorithm For Wireless Sensor Networks

Multicast communication has a huge advantage to reduce network resource consumption and increase data transmission rate, as the wireless sensor networks applications continue to expand, multicast routing algorithm have become an important branch of routing algorithm for wireless sensor networks.This dissertation is based on the research and analysis of the existing multicast routing algorithms for wireless sensor networks, considering the insufficiency of the multicast tree in the existing protocols whose communication overhead is relatively high, the transmission numbers and the distance of reach a single destination node that is needed in constructing muliticast tree are difficult to reach a copmpromise a new adaptive threshold parameter multicast routing algorithm is proposed.In the adaptive threshold parameter multicast routing algorithm, routing decision is based on node's location information, the nodes according to local network topology to select the next hop node as a forwarding node by greedy strategy. The algorithm is divided into two phases. The destination nodes are merged and partitioned optimally in the initialization stage. After the initialization, the effective path factor a of the corresponding destination nodes is calculated on the current source nodes. An adaptive threshold parameter P is selected to evaluateα. The next transmitted node of the current sources node is determined in virtue of the evaluating results until all the data packets were sent to the destinations.In the simulation, analysis the performance of the algorithm when simulation parameter changes that may affect the performance of the algorithm, and compared with the existing multicast protocol EbMRP, concluded that the proposed algorithm obtained better performance.In order to further study scalability of the adaptive threshold multicast routing algorithm, this dissertation proposes a new multicast routing algorithm based on destination region.The algorithm defined the region concept, tree-based multicast and multicast based on limited flooding had a very good combination in this algorithm, applied to the source node send interest message to multiple destination regions. The algorithm is divided into two phases, the first virtual tree-based multicast, using the basic theory of the adaptive threshold parameter multicast routing algorithm; the second phase execute constrained flooding multicast in the region.For this algorithm we have done a simulation experiment, simulation results show that the algorithm has good adaptability and the success ratio of the establishment of multicast tree is relatively large when the node density is appropriate.