A novel key update protocol in mobile sensor networks

Abstract

Wireless Sensor Networks (WSN) have found applications in many areas including healthcare, military and behavior monitoring. However, due to various factors (e.g. use of a wireless channel, deployment in public and unattended areas), WSN applications are vulnerable to various attacks such as impersonation, replay, selective forwarding and sink hole. Therefore, security is an important issue to protect data in WSN. Several symmetric key based security schemes have been proposed in WSN for node authentication and secure data delivery. Most of the schemes are applicable for static WSN, where nodes once deployed, are not allowed to change their locations. However, depending on the application requirements, nodes in WSN may require to move from one place to another. The problem of authenticated pair-wise key update in dynamic WSN has not been addressed adequately in literature. In this paper, we propose a key update protocol which securely updates the session key between a pair of nodes with the help of random inputs in mobile sensor networks. Initially, a unique master key is obtained using symmetric bi-variate polynomial shares. This key is further used in authenticating and establishing the pair-wise key between a pair of nodes. Random inputs from both the participating nodes are used to update the pair-wise key in the mobile WSN setup. The security analysis shows that the proposed protocol resists known-key, impersonation, replay, worm and sink hole attacks. The proposed protocol also provides forward secrecy, key freshness, and mutual key control. © Springer-Verlag 2012.