SAKE - Secure Authenticated Key Establishment in Sensor Networks

Master key schemes are a viable solution to establish pairwise shared secret keys in wireless sensor networks. In these schemes, a master key is preconfigured into each sensor node which is then used by each node to generate pairwise shared secret keys. In the literature so far, it is essential for each sensor node to keep master key in its memory during the entire phase of key setup. As soon as key setup completes, each node erases the master key from its memory. Although key setup phase of a node lasts for a small interval of time, it is not impossible for an adversary to compromise a node during this time. In this situation, the presence of master key can be disastrous. So the challenge is to protect a sensor network from compromise of master key during its key setup phase. We propose Secure Authenticated Key Establishment (SAKE) protocol that meets the above challenge by introducing an idea that master key need not to be kept by a sensor node for the entire key setup phase thereby shortening the master key compromise window. With the help of our proposed scheme, other attacks during key setup phase can also be avoided.