Now in the Lync Server 2010 the Director is a dedicated role that you can deploy more easily.
Why to use a Director in your deployment?
- Authentication moves from the Front-End to the Director, more security for remote user
- Can home the Webservices for device update services and the client version filter thats checks the version of the users client and handle the sign-in web tickets
- recieves the home front-end pool to the client in multi pool deployments
Internal Sign-In for User homed on Pool 1
|Authentication view for external|