Domain controller (Windows)

Domain Controller

In Windows NT and Windows 2000 networking, the Domain Controller is the server that responds to security authentication requests (logging in, checking permissions, etc.) within the domain. In Windows NT, the central domain controller was known as the Primary Domain Controller (PDC), of which there could only be one with this role; all other domain controllers were identified as Backup Domain Controllers (BDC). In Windows 2000, all domain controllers are theoretically equal.