Patent ID: 8296823

Claim:
A system for authenticating an end user of a user station arrangement requesting access to protected information, comprising: an access server and an authentication device, the user station arrangement supporting communication with the authentication device over a first communication channel of a radio network, wherein the user station arrangement further supports communication with the authentication device over a second communication channel; the authentication device is adapted to, at reception of a request for access to protected information from a user station arrangement, establish if the user station arrangement is reachable over the first communication channel; the authentication device is adapted to support a first authentication mode and a second authentication mode over the second communication channel; and the authentication device comprises a decision device configured to select which of the first and second authentication modes is to be used for a user station arrangement requesting access to protected information; wherein the user station arrangement comprises a mobile device and an access terminal; the first authentication mode has priority over the second authentication mode; the authentication device includes an examination device that includes the decision device and that is configured to establish if the mobile device is reachable over the first communication channel of the radio network; and the decision device is configured to use the second mode if the mobile device is not reachable over the first communication channel of the radio network.