L’optimisation du déploiement d’un RCSF pour une application de surveillance de sites

Abstract

Wireless Sensor Networks (WSNs) have become over the years a very attractive field of research. In fact, they had the attention of many researchers who have been interested in issues raised by these networks, such as energy, deployment, coverage, connectivity, routing, etc. WSNs are particularly characterized by their miniatur- ized aspect, which makes them stealthy, and have rapid deployment in accessible or inaccessible zones. WSNs, which are considered an emerging technology, have a wide variety of applications in various fields such as military, health, transportation, agriculture, etc. In this thesis, we address the problem of the deterministic deploy- ment of sensor nodes of a WSN dedicated to the monitoring of strategic sites such as an petroleum or nuclear sites or any sensitive building (government or other). We split the network nodes into two categories. Sentinel Sensor Nodes -SN-, deployed at the site boundary to detect intrusion, and Relay Nodes -RN- deployed within the site and relaying alerts generated by SNs up to Sink. Our first objective is to find the optimal node locations in order to assert the barrier coverage (site boundary), a lower cost connectivity, in terms of the number of hops crossed, from each sentinel node to the sink. This limitation on the number of hops crossed by an alert will have a positive effect on the consumed energy as well as the latency (end-to-end delay) of the alerts. The second objective is to reduce the number of deployed relays to reduce the cost of deployment. The problem was formalized as two BILP (Binary Integer Linear Program) that we solved using the CPLEX solver. We also evaluated our solution using the Castalia simulator. The results obtained are very satisfying, in terms of the number of hops crossed by an alert, and consequently in terms of latency and energy.