Is WsFederation necessarily SSO ? (.NET and WIF inside)

Question

I'm trying making a Identity Provider for a project in .NET 4.5, using wsFederation (with WIF). One of the statements we made is that it should not be a SSO solution.

I managed to get a basic version running (by taking the templates from 3.5 and adapting them to 4.5).

But now that it's done, i realize that it does SSO, and I don't see how it could not do it.

So my question : Is wsFederation necessarily SSO ?

Answer 1

The stated aim of WS Federation is "to allow different security realms to federate, such that authorized access to resources managed in one realm can be provided to security principals whose identities are managed in other realms."

SSO is not mandatory but it is the main reason people use WS Fed together with a STS (like ADFS).

On some STS, you can disable the STS functionality.