Cache based energy efficient strategies in mobile ad hoc networks

On-demand routing protocols (ODRPs) for mobile ad hoc networks utilize route caching in different forms in order to reduce the routing overheads as well as to improve the route discovery latency. This paper presents an analysis of the effects of different design choices for this caching in ODRPs in wireless ad hoc networks. Efficient energy conservation plays an important role in the performance of wireless ad hoc networks because mobile hosts in such networks are usually battery-operated. Caching, however, can considerably impact the system energy expenditure; for instance, disseminating information incurs additional energy burden. Our analysis is based on the dynamic source routing protocol (DSR), which operates entirely on-demand. We present a variation of the existing DSR protocol called DSR-CACHE (DSR-C). The modification to the existing DSR protocol is done mainly in the way it identifies the route and the updating of the same in the source node cache. Based on simulation, it is found that the energy efficiency in the energy aware DSR-C protocol gives considerably higher cache hit rate and higher percentage of reliable delivery of packets.