Seminar on Optimising ad-hoc Network: Broadcast and Routing functions
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In the framework of Growing NAVIS project, NAVIS Centre organizes a seminar with the following details:

Topic: Optimising ad-hoc Network: Broadcast and Routing functions;
Presenter: Prof. Francois Spies, University of Franche-Comté, France;
Time: 9am-10am, Wednesday, November 7th 2012;
Venue: Meeting room, R. 601, Level 6, Ta Quang Buu library building;

Abstract: A mobile ad hoc network (MANET) is a collection of mobile nodes communicating through wireless connections without any prior network infrastructure. In such a network the broadcasting methods are widely used for sending safety messages and routing information. To transmit a broadcast message effectively in a wide and high mobility MANET (for instance in vehicular ad hoc network) is a hard task to achieve. An efficient communication algorithm must take into account several aspects like the neighborhood density, the size and shape of the network, the use of the channel. Probabilistic strategies are often used because they do not involve additional latency. Some solutions have been proposed to make their parameters vary dynamically. For instance, the retransmission probability increases when the number of neighbors decreases. But, the authors do not optimize parameters for various environments. This work aims at determining the best communication strategies for each node according to its neighborhood density. It describes a tool combining a network simulator (ns-2) and an evolutionary algorithm(EA). Five types of context are considered. For each of them, we tackle the best behavior for each node to determine the right input parameters. The proposed EA is first compared to three EAs found in the literature: two well-known EAs (NSGA-II and SPEA2) and a more recent one (DECMOSA-SQP). Then, it is applied to the MANET broadcasting problem.
Additionally, multi-path routing should be considered in ad hoc network in order to realize better routing. Yet, only few multi-path ad-hoc routing protocols take into account the radio-interferences which might arise between two geographically close routes. Moreover, they generally only forbid the addition of interfering paths rather than looking for a different, more optimized, solution. NICE-MRP is a novel multi-path routing protocol for mobile adhoc networks giving efficient solutions with respect to physical radio-interferences between paths. This protocol discovers and stores several combinations of non-interfering multi-path routes.
The best multi-path route is used to transmit data, whereas alternative multi-path routes are kept to dynamically react to route breakages due to mobility and node failures. Compared to other well-known protocols, NICE-MRP presents good qualities in terms of latency, overhead and packet losses. Besides, these results end to be rather independent from the degree of mobility.