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Several other new settings are used when proxying and provide various kinds of policy controls familiar to SP operators, as well as new features to support remapping of potentially non-interoperable AuthnContext values. By default, the IdP operates in a fairly automatic fashion when proxying, such that any <saml2p:RequestedAuthnContext> element from an SP will be echoed essentially as-is to any upstream Identity Provider, and the data found in the incoming assertion will be echoed as-is back downstream. Since proxying is often used to firewall against interoperability problems and crosswalk between different communities of practice, functions can be plugged in to perform more flexible mapping of values, and some pre-existing machinery is in place to support this declaratively, as described in the AuthenticationConfiguration page. An additional hook was added in V4.1 that allows a similar function to be injected but with access to the entire request state to do more advanced things.
There are also a variety of settings related to delegation that are not shown above but can be found in the relevant API documentation.