I have developed a R-STS with Framework .NET 4.5 using WSFederationAuthenticationModule. This R-STS redirect the request to the correct identity provider (custom STS, ADFS, ecc). In the event WSFederationAuthenticationModule_SessionSecurityTokenCreated in the R-STS, I can see the correct token retrieved and validated. In the realm parameter there is the Url of the RP Web Site. How can I pass this token to the RP (Asp .NET Web Site) and authenticating the user?