Namespace

Netbios use a flat address space, while IP protocol use a hierachy address space

DNS use a hierachy namespace, while WINS use a flat namespace

In Windows 2000/2003 Active Directory, domain tree use contiguous namespace. Non-contiguous namespace is used by other domain trees in the same forest or a different forest. Like tree has a root, the domain tree has a root domain, which is unique to the forest. Root domain is also call top level domain in forest. By default, the TLD/root domains in the same forest use two way transitive trust to allow pass-thru authentication throughout the forest.



Multi forest can be created. This allows you to control which tree( DOMAIN TREE)are connected and share the resources, and which trees are separated so that user can not search GC for other forest.



A site is a combination of subnet; subnet consist of computer using the same grouping of IP address

A DC is a server has a copy of directory service