Optimization of Location Aware Routing Protocols for Wireless Adhoc Tactical Networks

Abstract

oaches available e.g. DSDV, DSR, OLSR, AODV, ABR, ZRP but these protocols are used depending on the nature of situation. Protocol we have used in our thesis is Adhoc on Demand Distance Vector Routing (AODV) which is a reactive protocol i.e. it creates routes as and when required. AODV protocol was developed by Nokia Research Center, University of California, Santa Bar- bara and University of Cincinnati by C. Perkins, E. Belding-Royer and C. Das. Algorithm of AODV states that when source node needs route to des- tination it broadcasts send request packet to all the nodes present in given geographic region and broadcasting method used is expanding ring search. Even when route breaks or invalidates, AODV rst checks route bu er to see if existing route could be used or not. If either existing route is stale or to- vi pography is changed due to mobility then again AODV uses broadcasting to discover the requested route. That means each time, when route is needed, the route request packet is broadcasted to all nodes which unnecessarily uses the bandwidth and processing at each node causing power bottleneck to arise. Therefore our thesis is focused on the optimization of AODV protocol by re- stricting packet broadcasting to conserve power of nodes. For this purpose, we have used Global Positioning System. By knowing coordinates of the nodes, our algorithm targets only that subset of nodes which are directly participating in route establishment. This modi ed algorithm limits route request packets which results drastic reduction in packet broadcasting and conserves power. Hence control packets are reduced whereas data transmis- sion increases which also increases performance. To simulate the algorithm we have used NS2 in Linux based platform. NS2 is basically mixture of TCL and C++ whereas OTCL provides linkage between TCL and C++. Back- end code is implemented in C++ language whereas TCL language is used to create front end layout by de ning number of nodes, their tra c pattern and their parameters e.g. transmission range, battery power etc. In the end, results of modi ed AODV are compared with traditional AODV and DSR.