Patent attributes
A user authentication method in a distributed processing system commences by receiving, at a first processing unit (108), a request (1004) to initiate an authentication session, wherein the request includes a unique identifier of a user requiring authentication. The first processing unit acquires at least one item of authentication data (412, 1712), which is valid during the authentication session. The authentication data is transmitted (1006) to a second processing unit (106) which is associated with a terminal device operated by the user. The second processing unit transforms the authentication data using a transformation algorithm based upon one or more session-specific authentication factors (404, 1704), to generate transformed authentication data that is characteristic of the authentication session and of the user. The transformed authentication data is transmitted (1008) to a third processing unit (108) which verifies that the transformed authentication data corresponds with the user and with predetermined values of the one or more session-specific authentication factors. The third processing unit generates an authentication result (1010) of the authentication session based upon the verification.
