I-ndmr Protocol In Manet Applications

Ad hoc routing protocols may generally be categorized as being either table-driven or on-demand-driven according to their routing strategy. Table-driven protocols require that nodes in a wireless ad hoc network should keep track of routes to all possible destinations so that when a packet needs to be forwarded, the route is already known and can be used immediately. On-demand-driven protocols only attempt to build routes when desired by the source node so that the network topology is detected as needed. NDMR (Node-Disjoint Multi-path Routing) bases on AODV(Ad Hoc On-Demand Distance Vector)and DSR(Dynamic Source Routing), is an On-demand routing protocol. Compared with AODV and DSR, it reduces routing overhead dramatically and achieves multiple node-disjoint routing paths. In default, NDMR will use the shortest node-disjoint path to communicate with destination until link break happens.In this work, I-NDMR(Improved Node-Disjoint Multi-path Routing) protocol is proposed, which aims to reduce the shared links between multiple sources and destinations.I-NDMR protocol will no longer choose the shortest path, and will choose a path with lowest load to send data packets. To achieve this, load evaluation and load update processes are added to original NDMR protocol to enable the source node to acquire the load information of each node-disjoint path. Load evaluation process evaluates the load of each node-disjoint path. Load update process periodically updates the load of each established node-disjoint path. The improvement will reduce the probability of congestion, balance the load of the network and increase the performance of network.The simulation compares the performance of NDMR protocol and I-NDMR protocol. Based on the routing process model of NDMR, Load_Eval and Load_Update states are added to the routing process model of I-NDMR, corresponding to the load evaluation and load update processes. As I-NDMR protocol chooses the path with lowest load to transmit data packet, the buffer wait time of data packets is reduced, simulation shows I-NDMR acquires lower data packet delay. Though load update process may increase routing overhead, simulation shows that there is little difference in routing overhead between the two protocols.