Techniques to enhance the MANET lifetime

Now-a-days more and more devices are getting portable. This have encouraged the development of mobile ad hoc networks (MANET). In addition to device portability, MANET does not require, a pre-established network infrastructure. As a result they can be easily deployed in situations like emergency rescue and disaster management.However, there are certain issues that are inherent to MANET such as hidden and exposed terminal problem, limited bandwidth, limited processing and battery power.These issues need to be addressed for successful deployment of MANET.Nodes in MANET are run by battery power. Sometimes, it is difficult to replace and/or re-charge the battery. Therefore, to increase the longevity of the network, the available battery power must be judiciously used. In this thesis we have proposed two techniques to enhance the lifetime of MANET. They are: (i) Distance Based Topology Control with Sleep Scheduling (DBSS), and (ii) Alternate Path based Power Management using Clustering (APMC).DBSS is based on topology control method. In DBSS the network topology is modified by adjusting the node’s transmission power. Nodes that is geographically closer to the destination node is selected as the next-hop node for routing the traffic. Nodes that are not involved in on-going transmission are put to sleep state, to conserve energy. APMC is based on transmission power management method. In APMC node disjoint alternate paths are computed. The traffic is routed through k-alternate paths,so that no nodes on a path depletes its energy at a faster rate than other nodes. A clustering mechanism is employed to control the routing activity. The network is logically divided into number of clusters. A node within each cluster is selected as cluster-head. In the absence of traffic cluster-head put the nodes on that path to sleep state to conserve energy. We have compared the proposed schemes, with existing ones through simulation. It is observed that, the proposed scheme can enhance the longevity of the network. Simulation is performed using Qualnet simulator