1. A client that needs to look up an Active Directory name first passes the DNS
part of the name to a standard DNS server. The DNS server returns the network
address of the domain controller responsible for that name.
2. Next, the client uses LDAP to query the domain controller to find the address
of the system that holds the service the client needs.
3. Finally, the client establishes a direct connection with the requested service
using the correct protocol required by that service.