PERFORMANCE EVALUATION AND COMPARISON OF DSR, MDSR AND RDSR ROUTING PROTOCOLS

Mobile Ad Hoc Network (MANET) have many complex problems, one of this problems is routing. The main sources of routing complexity come from nodes mobility, limited power source and bandwidth, and jamming that lead to frequent changed topology of network. Many research articles have been done to mitigate the effect of the dynamic topology on the route stability among nodes of network. One of the well-known routing protocols of MANET is Dynamic Source Routing protocol (DSR). It is reactive routing scheme, where the route is selected based on the minimum hop counts, as a metric, between the source and destination node. In this context, most research papers showed that the route selection based on minimum hop counts, as a criteria, have little positive effect on the route stability of DSR protocol. Therefore, there are various enhancements have been carried out on the original DSR protocol to obtain more stable routes among the nodes in the dynamic environment of MANET. This paper presents performance evaluation and comparison between the original DSR and two enhanced versions of DSR. The two enhanced versions are called Modified DSR (MDSR) and Reliable DSR (RDSR), and their operation is based on Cross Layer Design (CLD) technique which allows information sharing between the routing layer and the physical layer. MDSR is concerned with modification of the route discovery phase, where the route selection is based on the measured signal strength of route reply packets on the route links instead of the number of hops count. Also, unlike DSR, the route is selected by the source node instead of the destination node. On the other hand, RDSR is concerned with modification of route maintenance phase, where any intermediate node, along the route, has the ability to early predict the route failure before data packets lose resulting in the reduction of routing control packets. The comparison and performance evaluation of MDSR and RDSR versus DSR have been carried out using network simulator NS2 (ver. 2.35), under Ubuntu 10.4.