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You can see much of the information established by Shibboleth for use by an application by accessing that application's "Session" handler: visit, e.g., https://your-host/Shibboleth.sso/Session after delivering an assertion running through the login process.
An application that has been enabled to rely on standard HTTP environment information such as "REMOTE_USER" is essentially already prepared for use with Shibboleth. (We maintain a partial list of common commercial applications that have been enabled already.)
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