Mutual authentication system

Abstract

A wireless communication system enables one-sided authentication of a responder device () by an initiator device () and mutual authentication of both devices. Embodiments of the initiator may have a message unit () and a state machine (). The initiator starts by acquiring a responder public key via an out-of-band action and sends an authentication request. The responder sends an authentication response comprising responder authentication data based on a responder private key and a mutual progress status indicative of the mutual authentication being in progress for enabling the responder device to acquire an initiator public key via a responder out-of-band action. The initiator state machine is arranged to provide a mutual authenticating state, engaged upon receiving the mutual progress status, for awaiting mutual authentication. Thereby long time-out periods during wireless communication are avoided, while also enabling the initiator to report communication errors to the user within a short time.