Working with a Central Authentication Service

I am developing a community-based website using Joomla and the Community Builder extension which ideally will work with a Central Authentication Service. While there is a set of plugins for Joomla and CB, the idea of replacing the Administrative and Frontend logins with an anonymous set of extensions found on the web, then not being to get back into the site scares the heck out of me.

Has anyone worked with a CAS? I think you need to be a server guru even to undertake it.