When the AD FS role is installed, there are a few related components we need to be aware of. Before Windows Server 2012 R2, there were four AD FS roles services: the federation service, the federation service proxy, the claim-aware agent, and the Windows token-based agent (which supports the AD FS 1.x interoperability). These are no longer available as role services, and when we go to install AD FS, it will only have the federation service role.
AD FS components
Federation service
This is the main role service for AD FS, and it can work at the IdP end as well as the SP end. In order to install the AD FS role service, the system needs to be a member server of an AD domain. Depending on the workload, multiple federation servers...