Congestion Aware and Adaptive Dynamic Source Routing Algorithm with Load-balancing in MANETs

The explosive growth in the use of real-time multimedia applications in mobile devices requires quality of service (QoS) support for effective communication. Network congestion is the main reason for packet loss, longer delay and jitter in streaming multimedia applications. Most of the present routing protocols are not designed to adapt congestion. In this paper, the original DSR protocol is modified to define the occurrence of congestion by monitoring and reporting multiple resource utilization thresholds as QoS attributes and use multi-path-routing and load-balancing during the periods of congestion to improve QoS in MANETs for CBR multimedia applications. NS-2 simulation was extensively carried out to evaluate the performance of the modified DSR in terms of throughput, jitter and end-to-end delay. The results were compared with the original DSR in random node movements under varying traffic loads of 10, 15 and 20 CBR traffic flows to completely assess the applicability of the modified DSR. Simulation results showed that the proposed protocol can significantly improve the network performance for low and medium traffic load in multimedia based mobile ad hoc networks by extending the network lifetime and providing fewer packet losses than the original DSR.