Virtual patrol: a new power conservation design for surveillance using sensor networks

Surveillance has been a typical application of wireless sensor networks. To conduct surveillance of a given area in real life, one can use stationary watch towers, or can also use patrolling sentinels. Comparing them to solutions in sensor network surveillance, all current coverage based methods fall into the first category. In this paper, we propose and study patrol-based surveillance operations in sensor networks. Two patrol models are presented: the coverage-oriented patrol and the on-demand patrol. They achieve one of the following goals, respectively, i) to achieve surveillance of the entire field with low power drain but still bounded delay of detection; ii) to use an on-demand manner to achieve user initiated surveillance only to interested places. We propose the "SENSTROL" protocol to fulfill the patrol setup procedure for both models. With the implementation in the GloMoSim simulator, it is shown that patrol on arbitrary path can be set up in a network where each node follows a 98%-time-sleep-2%-time-wake power schedule.