A resilient and seamless rekeying scheme based on random key distribution for WSN

Wireless sensor networks are often placed in hostile and unattended areas, making the nodes exposed to many attacks. Node capture is one of the prominent attack in such networks. Whenever, a node is captured, its keys have to be revoked from the network by means of rekeying. We aim to optimize the problem of key revocation and rekeying by reducing the communication and computation overhead. An attack algorithm is presented from an adversarial view point, compromising of capturing cost and traveling cost. It is used to compute the destructive rank of each node which ultimately finds the set of vulnerable nodes of the network. Each communicating node determine a backup key for future node revocation and automatically switches to it, to avoid the reconfiguration of the shared key. The keys of vulnerable nodes are bypassed during the generation of the backup link keys. It is shown that proposed scheme has high level of security as well as reduced communication overhead during rekeying process. The proposed attack is also compared with random attack and found that it is improved in terms of route compromise ratio and energy cost.