A new dynamic user authentication scheme using smart cards for wireless sensor network

As an essential part of security needs of wireless sensor networks, user authentication is used to make sure only the legal user can access the data from the sensor/gateway node. Recently, several dynamic user authentication schemes for wireless sensor networks were proposed. It can be seen that these schemes have weaknesses because of using timestamps. Implement of strict and safe time synchronization is very difficult and increases network overhead. We propose a new dynamic user authentication based on nonces instead of timestamps. In the scheme, mutual authentication is performed using a challenge-response handshake between user and gateway node in both directions, and it avoids the problem of synchronism between smart card and the gateway node. Analysis shows its robustness to various attacks and requires much less computation. What's more, the scheme provides key agreement between user and gateway node.