adaptive strategies for efficiently locating internet-based servers in manets
Providing Internet access to Mobile Ad hoc Networks (MANETs) can greatly extend their applications, increase their scalability, and improve the quality of service. However, a critical problem is how the mobile hosts can locate Internet-based servers efficiently in a dynamic, unstructured network. Neither reactive strategies, where the hosts initiate on-demand server discovery, nor proactive strategies, where the servers periodically advertise their availability information, are optimal. To that end, this paper studies adaptive strategies that (1) combine both proactive advertising by the servers and on-demand discovery by the mobile hosts, and (2) determine the relative rate of proactive advertising and on-demand discovery adaptively according to the network characteristics including the host mobility level and the offered load. We propose and evaluate two novel, integrated algorithms. First, to determine the rate of proactive advertising, we propose an exponential backoff algorithm to probe the optimal operating point. Second, to reduce the network traffic due to reactive (on-demand) discovery, we propose a novel controlled flooding algorithm. Our simulation study reveals that, compared to the previous proactive strategies and reactive strategies, our adaptive strategies reduce network traffic for locating the servers by several times when the network has a moderate offered load and a low or high level of host mobility.
mobile ad hoc networks controlled flooding search algorithms