Dynamic Path-Switching: A Multiple Constrained QoS Routing Algorithm for Manets

The rapid development of communication systems in the last few decades has increased the deployment of multimedia and real-time applications within it. These applications require the support of Quality of Service routing algorithms that support multiple constraints to provide a service the meets the user expectations. Applying QoS on mobile ad-hoc networks (MANET) raises the challenge because of MANET’s dynamic nature. In this paper, a novel QoS routing algorithm is proposed, called Dynamic Path-Switching algorithm (DPS). DPS expands the normal QoS routing algorithms by trying to prevent path breakage instead of trying to maintain them. First, DPS discovers all paths that satisfy the QoS constraints for a particular service and chooses the highest stability. After sending data on the optimal path, DPS re-generates a path discovery request. When a new path is found, DPS starts sending data on it and discards the old path. This mechanism reduces path breakage because it changes transmission to new path before the old path breaks. DPS is simulated again AODV and MAODV in NS-2 simulator where simulation results showed that DPS performs better than both AODV and AOMDV algorithms. Simulation results also show that DPS is scalable and performs well in high mobile environments.