Application of DHT-Inspired Routing for Object Tracking

A major problem in tracking objects in sensor networks is trading off update traffic and timeliness of the data that is available to a monitoring site. Typically, either all objects regularly update some central registry with their location information, or the monitoring instance floods the network with a request when it needs information for a particular object. More sophisticated approaches use a P2P-like distributed storage structure on top of geographic routing. The applicability of the latter is limited to certain topologies, and having separate storage and routing algorithms reduces efficiency. In this paper, we present a different solution which is based on the scalable source routing (SSR) protocol. SSR is a network layer routing protocol that has been inspired by distributed hash tables (DHT). It provides key-based routing in large networks of resource-limited devices such as sensor networks. We argue that this approach is more suitable for object tracking in sensor networks because it evenly spreads the updates over the whole network without being limited to a particular network topology. We support our argument with extensive simulations.