A SAML reverse proxy is a service that acts as an intermediary between a SAML service provider (SP) and one or more SAML identity providers (IdPs). It can perform various functions, such as authentication, authorization, load balancing, caching, etc. One scenario where you would use a SAML reverse proxy is when there are multiple SAML IdPs in use and the SAML reverse proxy can help federate them all together. For example, suppose you have an internal application that needs to authenticate users from different domains or organizations, each with their own SAML IdP. Instead of configuring the application to trust each IdP separately, you can use a SAML reverse proxy to act as a single SP for the application and a single IdP for the users. The SAML reverse proxy can then redirect the users to their respective IdPs for authentication and relay the SAML assertions back to the application. This way, you can simplify the integration and management of multiple SAML IdPs and provide a seamless user experience. References: SAML Reverse ProxyWhat is application proxy & SAML SSO?