Research On Multipath Routing Protocol In Mobile Ad Hoc Networks

Mobile Ad hoc network is a kind of mobile multi-hop, self-organized and distributed wireless network. There is no network administration and static infrastructure so that they can be quickly built up anywhere or anytime. Ad hoc network needs network routing protocols those are suitable for its own features in the application. Multipath routing protocols can meet the requirements of fault tolerance, routing durability and QoS better than the single routing protocols, so that they are being hot issues around the world.Firstly, Backup Source Routing protocol is further analyzed and researched. According to the broken chain problem in BSR, a strategy considering the link service time to choose routes is proposed. For the problem that sub-paths of backup routes in the route cache take up a lot of storage space and increase the overhead, the strategy that using sub-path of routes from the common nodes to the destination node to send data is put up. The structure of routes is improved at last.Secondly, BSR-LST is forward based on BSR protocol. BSR-LST predicts the link service time with respect to the mobility of nodes to choose an optimal primary route with comprehensive consideration of the delay and the link service time, and then use cost function to choose a backup path which has the minimum route correlation with the primary path in the route discovery. Only when the primary path fails, the data will be sent on the backup path or sub-paths. If all the routes we have chosen fail, the source node will launch a new route discovery.Finally, the performance of BSR and BSR-LST are compared through the experiments. The simulation platform is NS-2. The simulation results show that BSR-LST protocol has better performance than BSR protocol such as route durability, packet delivery and route overhead.