Network decoupling: A methodology for secure communications in wireless sensor networks

Many wireless sensor network (WSN) applications demand secure communications. The random key predistribution (RKP) protocol has been well accepted in achieving secure communications in WSNs. A host of key management protocols have been proposed based on the RKP protocol. However, due to the randomness in key distribution and strong constraint in key path construction, the RKP-based protocols 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 address this problem. With this methodology, a WSN is decoupled into a logical keysharing network and a physical neighborhood network, which significantly releases the constraint in key path construction of the RKP protocol. We design two new key management protocols, that is, RKP-DE and RKP-DEA, as well as a set of link and path dependency elimination rules in decoupled sensor networks. Our analytical and simulation data demonstrate the performance enhancement of our solutions from the perspective of connectivity and resilience and its applicability in nonhighly dense sensor networks. © 2007 IEEE.