Evaluation of MANET Routing Protocols: Effects of Terrain Dimensions and Network Scalability

Mobile Ad-hoc NETworks or MANETs are a category of wireless networks. These networks do not use any infrastructure unlike traditional wired networks, and the data packets are sent over to the destination as multi-hop. Since the network is ad-hoc, it uses mobile nodes to forward the data packets which lead to the formation of several topologies, making the network dynamic in nature. Terrain dimensions are used for an area of land or a type of land when considering the physical features of a designed scenario. Because of the dynamic nature, MANETs may quickly scale to handle a high number of nodes, making them ideal for large-scale applications. They can also handle dynamic changes in network topology, such as adding or removing nodes. This dynamic nature of the network makes the traditional routing protocols inefficient and of no use in this case. Furthermore, the number of mobile nodes to be added or removed from the network over different terrain dimensions makes MANETs scalable in nature. Hence, in this study, we discuss the performance analysis of MANET routing protocols over different scalability levels and terrain dimensions by using the NS-3.27 simulator. The major contribution of this research work is to analyze these two important network factors which may help to the researchers to use this study as a base to do further experimental work on other ad-hoc networks. The various metrics over which the performance of these routing protocols is measured are Throughput, Goodput, Receive Rate and Packets Received. Over the designed scenario, the selection of the best routing protocol is achieved. It is observed that in small terrain dimensions, Dynamic Source Routing (DSR) protocol is best suited. In medium terrain areas, Optimized Link State routing protocol (OLSR) acted as the best routing protocol and for large terrain areas, Ad-hoc On-demand Distance Vector (AODV) is considered as the best routing protocol.