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CAS provides an example user interface that's designed to run in any container that supports the Servlet 2.4 specification. A good container is the Tomcat 5.x series, though any 2.4 servlet container will work. CAS will run on earlier versions of Tomcat e.g. 4.x if the older style JSTL tags are used. It would be easier to use the newer Tomcat version.
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The CAS Mechanism
The CAS authentication and service registry is a secure way to authenticate users and provide web application or web service access. Authentication credentials are managed by the CAS server and your application servers never touch this information. User access to your application is quite involved. A multi-request approach adds a layer of security and truly logical mechanism where authentication is isolated from the application.
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