US Patent 10298759 Contact center user authentication

A method comprising: establishing a first session with a user; determining a unique identifier of the first session; generating a session identifier to identify the first session and storing it in a cache in association with the unique identifier; outputting an address and the session identifier, for delivery to the user; receiving an authentication request transmitted to the address from the user's first device, and in response, outputting a message to the first device, the message comprising the session identifier and an address at which a request for authentication by an authentication service can be directed; receiving an authentication success message comprising the session identifier and indicating authentication of the user; establishing a second session with a service agent; and in response to receiving the message, querying the cache with the session identifier to determine the unique identifier, and connecting the first and second sessions together using the unique identifier.