A key distribution scheme preventing collusion attacks in ubiquitous heterogeneous sensor networks

Random key pre-distribution schemes are vulnerable to collusion attacks. In this paper, we propose a new key management scheme for ubiquitous heterogeneous sensor networks consisting of a small number of powerful high-end ℋ-sensors and a large number of ordinary low-end ℒ-sensors. The collusion attack on key pre-distribution scheme mainly takes advantage of the globally applicable keys, which are selected from the same key pool. As a result, in our scheme, after discovering the shared pairwise keys with neighbors, all ℋ-nodes and ℒ-nodes destroy their initial key rings and generate new key rings by applying one-way hash function on node's ID and initial key ring. The analysis of proposed scheme shows that even if a large number of nodes are compromised, an adversary can only exploit a small number of keys nearby the compromised nodes, while other keys in the network remain safe. It outperforms the previous random key pre-distribution schemes by considerably reducing the storage requirement, while providing more resiliency against node capture and collusion attacks.