Performance Study on Two Distance Vector Routing Protocols for Mobile Ad Hoc Networks

Abslract-We investigate via simulation the performance issues of Dcstinatioo-Sequenced Distance Vector (nSDV) and Ad-hoc On-demand Distance Vector (AODV) routing protocols for mobile ad hOl: networks. Four perfonnance metrics arc measured by varying the maximum speed of mobile hosts, the number of connections, and the network size. Monle Carlo simulation method is used to estimate the expectation values of perfonnance metrics. The correlation between network topology changes and mobility is investigated by using linear regression analysis. The simulation results indicate that AODV outperforms DSDV in less stress-ful situations, while DSDV is more scalable with respect to the network size and traffic load. It is observed lhat network congestion results in more than half of the dropped packets for both protocols. Our observation indicates that always sending packets through the shortest routes might cause congestion in sparse networks, but rarely in dense ones. The investigation demonstrates that reducing broadcast intefYals from 15 seconds to 8 seconds improves the lhroughput of DSDV by about 10%, and shows that using longer packet queues does not help.