System and method for computer authentication using image analysis of a shared secret

摘要

Client and server computers on a network can be authenticated using a shared secret. During a log-on and authentication process, the server transmits an image to the client. A mobile communication device captures and analyzes the image. If the image contains the shared secret, the mobile device can authenticate the server. The secret in the image can be a geometric relationship between elements of the picture, a mathematical relationship between elements, a particular number or types of elements in the picture, colors of elements, or combinations of the above. A single image may contain multiple shared secrets. The mobile device can readily analyze the image to determine if it contains the shared secret and thereby authenticate the server.