A Probabilistic Routing Protocol for Heterogeneous Sensor Networks

The past five years witnessed a rapid development in wireless sensor networks, which have been widely used in military and civilian applications. Due to different requirements in their application environment, sensors with different capacities, power, and so on are deployed. Data routing in such heterogeneous sensor networks is a challenging task. On one hand, the heterogeneous features bring about the diversity in their transmission ranges, which subsequently lead to asymmetric links in the communication graph. As a result, conventional routing strategies based on undirected graphs become unsuitable. On the other hand, sensors communicate with each other through intermittent asymmetric links. It is important to provide assurable delivery rate for mission critical applications. In this paper, we propose ProHet: a Probabilistic routing protocol for Heterogeneous sensor networks, which can deal with asymmetric links well and work in a distributed manner with low overhead and assurable delivery rate. The ProHet protocol first produces a bidirectional routing abstraction by finding a reverse routing path for every asymmetric link. Then, it uses a probabilistic strategy to choose forwarding nodes based on historical statistics, which is shown to achieve assurable delivery rate by theoretical analysis. Extensive simulations are conducted to verify the efficiency of the proposed protocol.