Abstract
A novel design of secure end-to-end routing protocol in wireless sensor networks was recently proposed by Harn et al. Their design is based on a group key pre-distribution scheme (GKPS) using a multivariate polynomial. A group key also called a path key, is used to protect data transmitted in the entire routing path. Specifically, instead of using a link-to-link secure communication that uses multiple pairwise shared keys, it is an end-to-end secure communication that uses a single path key to protect data over the entire path. The problem with all polynomial-based key distribution schemes is that the security of these schemes, which are called deterministic k-secure, depends on the degree of the chosen polynomial. In other words, if the degree of the chosen polynomial is k, then capturing the k + 1 sensors (or more) can compromise the system's security. Although increasing the degree of the polynomial can improve the security, it increases the storage and computational requirements of the sensors. In this paper, we propose the first probabilistic polynomial-based GKPS, which is based on a multivariate polynomial. The security of our scheme is probabilistic k-secure, which means it is probabilistic to compromise the security of our GKPS after capturing the k + 1 sensors. We show that the probability of a sensor capture attack can be significantly reduced.