Patent ID: 8893243

Claim:
A method, implemented by a computer-implemented authentication system, for authenticating a user attempting to access a target component of a computer system from a first user system, the first user system being connectable to a first communications network, the method comprising: receiving, by at least one computing device, user authentication information entered by the user via a first user-interface of the first user system; obtaining, by the at least one computing device, via the first communications network a session identifier and at least one item of contextual information identifying the first user system or a property of the first communications network; verifying, by the at least one computing device, the user authentication information, and responsive to successful verification of the user authentication information, sending a message from the computer-implemented authentication system via a second communications network to a second user system, the message comprising (a) at least one item of said obtained contextual information or derived information of said obtained contextual information, allowing the second user system to present at least the at least one item of contextual information to the user via a second user interface so as to allow the user to verify the at least one item of contextual information, and (b) a real-time session-specific one-time passcode, different from the at least one item of said obtained contextual information, and associated with the session identifier; receiving, by the at least one computing device, via the first user system and the first communications network a passcode entered by the user into the first user system; verifying, by the at least one computing device, the entered passcode against the real-time session-specific one-time passcode and/or the session identifier; and responsive to a successful verification of the entered passcode, granting to the first user system access to the target component.