Abstract: A user, by way of a computing device, requests and receives content from a first server at the computing device. An authentication response is also received from the first server at the computing device of the user. The authentication response includes an address of the second server and an executable script. The computing device of the user executes the executable script by issuing a request to the second server for state information corresponding to the user, receiving the state information from the second server; and determining, based on the state information, whether the user is authenticated to the second server. If the user is not authenticated to the second server, the computer device of the user displays a login module that is visually associated with the first server. Such login module collects login information for authenticating the user to the second server.

Abstract: A method of in-line sign in that allows a user to sign into a first server based on a sign-in methodology of a second server is disclosed. The method uses, among other things, a nonce and approved URL list to prevent spoofing and replay attack. Additionally, the method allows error messages that occur during the authentication process to be displayed to the user having the look and feel of the first server, despite using the authentication process of the second server. A method of dual or distributed authentication is also disclosed wherein the user need only to input the login id and password once and wherein the two authentication processes need not exchange the user's password.