An Energy Efficient Search in Dense Wireless Sensor Network

Since sensor networks can be thought of as a distributed database system, several architectures proposed to interface the application to the sensor network through querying protocol. However sensor networks are so massively distributed, so careful consideration should be put into the efficient organization of data and the execution of queries. Here we consider the problem of information discovery in a densely deployed wireless Sensor Network (WSN) where the initiator of search is unaware of target information. A new type of protocol based on Increasing Ray Search (IRS) which is an energy efficient and scalable search protocol is discussed. The basic principle of this protocol is to route the search packet along a set of trajectories called rays that maximizes the likelihood of discovering of the target information by consuming least number of transmission. The rays are organized such that if the search packet travels along all these rays, then the entire terrain area will be covered by its transmissions. We compare IRS with existing query resolution techniques for unknown target location such as, Expanding Ring Search, Random Walk Search, and Gossip Search. We prove by theoretical analysis that IRS is independent of node density.