Cross-layer based routing protocol and solution to packet reordering for TCP in MANET

In mobile ad hoc networks (MANETs), link failures and route changes occur most frequently, which may result in packet reordering. Transmission control protocol (TCP) performs poorly in such environment, which misinterprets the reordered packets as lost packets due to congestion. This has motivated us on developing a new protocol towards the packet reordering for improving the performance of TCP in MANETs. Optimal path or route selection is the major concern to improve the energy efficiency and network lifetime. In this paper, trust aware routing protocol for selecting optimal route in MANET is proposed. Based on this protocol, trust value for each node is calculated using direct and indirect trust value. Then the routing cost metric value is calculated and the path with minimum cost metric value is chosen as the best path in the network. After selecting the optimal path, data packet is to be transmitted through the optimal path. During the transmission, the data packet may get dropped or reordered due to congestion or mobility. A cross layer approach between network layer and transport layer to identify the dropped and reordered packets in the network is proposed in this paper. Simulation results are reported, which support this proposal.