Key establishment and management for WSNs

Abstract

Wireless Sensor Networks (WSNs) are composed of a large number of low-cost, low-power, and multi-functional sensor nodes that communicate at short distances through wireless links. Those networks could be deployed in an open and hostile environment where attackers may be present. In this context, it is necessary to guarantee confidentiality, integrity and security services in the network. Those security properties could only be achieved if security associations have been created in the network between pairs of nodes, each node and the base station of groups of nodes. Those associations are created through key management protocols for pairwise or group establishment, distribution, renewing of cryptographic keys. Those protocols must only use information that is available in the network or pre-loaded in each sensor as the WSNs mus be autonomous. Moreover, due to the low-cost nature of each node, an attacker is able to compromise nodes because the nodes are not tamper-resistant. Thus a major challenge of the key management protocols becomes to preserve the general security of the network even if t nodes are compromised. We propose in this article a key management and access control protocol based upon a group deployment model. Moreover, this protocol is t-secure, i.e. t corrupted nodes are not sufficient to corrupt all the keys used in the network.