The Active Directory deployment has a single domain, gt.com, with two domain controllers located in the United States and two in Europe. The user information is stored in the standard cn=users container in Active Directory (cn=users,dc=gt,dc=com).
The Active Directory samaccountname attribute value matches the Directory Server uid attribute. The Active Directory domain controller with the PDC FSMO role is located in the United States office.
Both ad1-us.gt.com and ad3-eu.gt.com are bridgehead servers that control replication between the two sites.