Starting with DotNetNuke v3.3/4.3, all dependencies on the Microsoft MemberRole assembly were removed. DotNetNuke includes a Role Provider, a Profile Provider and a Member Provider that works directly with ASP.Net membership. When the MemberRole dependency was introduced in DotNetNuke v3.x, many portal administrators who used the multi-portal Single Sign-On capability in DotNetNuke v2.x had to resort to third-party solutions to make SSO work across portals. With DNN v4.3 (possibly v3.3 also; I have not tested), it looks like SSO, or at least the potential for SSO is back.

If you add a row for a user in the UserPortals table, the user will effectively be able to authenticate seamlessly to every portal for which her/his user ID has a portal ID assigned. It’s that simple. Everything works as you would expect — roles are portal-specific; the user’s profile is portal-independent and authentication works regardless of which portal a user initially logs into.

Implementing a UI for administering SSO looks to be as simple as having a module where you can link/unlink users to/from portals. Nice.