Parametric-based mobility for providing opportunistic geocasting in spatially separated wireless sensor networks

Uneven deployment and environment constraint leads to the formation of a spatially separated wireless sensor network (SS-WSN). Most of the traditional WSN architectures consist of static nodes that are densely deployed over a sensing area and are fully connected. SS-WSN is a group of disjoint subnetworks where connectivity is generally maintained by energy rich mobile nodes (ERMN), which roam about from one subnetwork to another. We propose an algorithm whereby the mobility of ERMN helps in distributing the geo message opportunistically in the region of interest. The routing consists of two phases: (1) transmission of the geo message from the source node to the ERMN based on a proactive mobility predictive scheme (PMPS) within a subnetwork (intra-routing); (2) relaying the geo message from the source subnetwork to the destination subnetwork (inter-routing). This is achieved with the help of an ERMN that traverses on a parametric curve, visiting each subnetwork. The key issue addressed here is to minimize latency and improve reliability, thereby keeping the network virtually connected at variable period of time. Extensive simulation shows that the proposed solution performed better than random path-based mobility routing.