Minimization of Congestion using Backpressure Routing Algorithm in Wireless Networks

Back-pressure-type algorithms have recently received much attention for jointly routing and scheduling over multihop wireless networks. However, this approach has a significant weakness in routing because it explores and exploits all feasible paths between each source and destination. While this extensive exploration is essential in order to maintain stability when the network is heavily loaded, under light or moderate loads, packets may be sent over unnecessarily long routes, and the algorithm could be very inefficient in terms of end-to-end delay and routing convergence times. We develop a improvised backpressure routing algorithm that maximizes network throughput and expends an average power that can be pushed arbitrarily close to the minimum average power required for network stability, with a corresponding tradeoff in network delay .This paper proposes a new routing/scheduling back-pressure algorithm that not only guarantees network stability, but also adaptively selects a set of optimal routes based on shortest-path information in order to minimize average path lengths between each source and destination pair . On the other-hand, the proposed algorithm adaptively selects a set of routes according to the traffic load so that long paths are used only when necessary, thus resulting in much smaller end-to-end packet delays as compared to the traditional back-pressure algorithm.