Achieving energy efficient and secure communication in wireless sensor networks

Wireless sensor networks (WSN) are increasingly become viable solutions to many challenging problems and will successively be deployed in many areas in the future such as in environmental monitoring, business, and military applications. The huge challenge in WSN is due to inherent resource and computing constraints. Because the sensor nodes are battery powered, increasing the autonomous lifetime of a WSN is a challenging optimization problem. Transmission of data is one of the most energy expensive tasks a node undertakes - using data compression to reduce the number of bits sent reduces energy expended for transmission. Data compression which highly reduces the communication overhead by aggregating and compressing data packets is performed at intermediate sensor nodes. However, deploying new technology, without security in mind has often proved to be unreasonably dangerous. The problem of securing these networks emerges more and more as a hot topic. Symmetric key cryptography is commonly seen as infeasible on such networks. Public key cryptography has its own key distribution problem. In contrast to this prejudice this paper presents a method to increase the lifetime of a WSN by minimizing the energy cost of transporting information from a set of sources nodes to the sink nodes and for achieving security we have used a new public-key encryption technology called identity-based encryption (IBE) which allows to calculate a public key directly from a user's identity. By calculating public keys instead of generating them randomly, many of the difficulties that make encryption technology difficult to deploy and maintain are eliminated, making encrypted communications much easier to implement than in the past.