Network Decoupling for Secure Communications in Wireless Sensor Networks

Secure communications are highly demanded by many wireless sensor network (WSN) applications. The random key pre-distribution (RKP) scheme has become well accepted in achieving secure communications in WSNs. However, due to its randomness in key distribution and strong constraint in key path construction, the RKP scheme can only be applied in highly dense networks, which are not always feasible in practice. In this paper, we propose a methodology called network decoupling to solve this problem. With this methodology, a wireless sensor network is decoupled into a logical key-sharing network and a physical neighborhood network, which significantly releases the constraint in key path construction of the RKP scheme. We design a secure neighbor establishment protocol (called RKP-DE) as well as a set of link and path dependency elimination rules in decoupled wireless sensor networks. Our analytical and simulation data demonstrate the performance enhancement of our solution and its applicability in non-highly dense wireless sensor networks