what component of the NiC (network card) settings is necessary for domain controllers to communicate and member machines to join the domain?

Potential Trivial Pursuit Questions (Type and upload to D2L drop-box): 1. What component of the NIC (network card) settings is necessary for domain controllers to communicate and member machines to join up to the domain? 2. What is the name of the directory (Foider) that holds the Active Directory Database? 3. Can any user account on the server allow a machine to join the domain? Why would you want control over who can join a machine to the domain? 4. What do you get from a domain that you don't get from a stand-alone Workgroup computer? 5. What is an Active Directory Forest