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The YaleCasFilteredContext is part of the Yale uPortal CAS security provider package, available here.
Proxying authentication
The above instructions should get you to the point where users can authenticate to your uPortal itself using CAS. A killer feature for portals that CAS offers beyond this initial authentication is proxy authentication. In this section we describe the additional configuration you need to make to turn on proxy authentication. We highly recommend that you first verify that you are able to CAS authenticate to your uPortal istself before tackling the additional complexities of proxy authentication.
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