Instituto Superior Técnico

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Authentication CAS

The Central Authentication System (CAS) developed at Yale University is an authentication system that intermediates authentication requests between web pages and centralized authentication systems at IST.

CAS allows:

  1. Each user to use a single credential access (Técnico ID and password);
  2. On the other hand allows any user to condition access to their webpages by setting up the authentication mechanisms.

Besides managing the authentication requests that are made at the level of the HTTP layer, CAS also allows a user to keep an authenticated session for two hours and maintains the same session in several different web pages (since it is a Single Sign-On system).

The use of CAS authentication service is available to the whole IST community however to condition use and secure access users must submit a request by email to DSI with the following information:

  •     Service designation;
  •     Login address – the URL that will be sent to CAS server parameter “service”;
  •     Logout address – the URL that is called to terminate or invalidate the application session (this URL address should only destroy the session and should not call the logout function of CAS library).

Once provided the authentication mechanisms it will be the service or requesting user to configure the necessary code in the respective webpages.