Active Directory

With the introduction of Windows 2000, Microsoft introduced Active Directory. Active Directory can be described as a hierarchical directory system, broadly similar in concept to Novell's Directory Services or the X.500 directory system. Among the uses of Active Directory is management of resources in a CIFS network; facilities such as the traditional browser service can be "replaced" by Active Directory. Because Active Directory has a significant impact upon CIFS networking, a brief overview is presented here, however a full description is beyond the scope of this documentation; there are many excellent references on Active Directory.

As described above Active Directory (AD) implements a "tree structure" of objects that is broadly analogues to other directory systems that use "X.500" type technology. Indeed Active Directory is implemented using other standard directory technologies. In particular AD makes use of the Domain Name System (DNS) to establish an overall hierarchical tree structure. The Lightweight Directory Access Protocol (LDAP) directory system is also used to provide further granularity and provide facilities not available in the DNS. Traditional NT Domain technology is also used and provides backwards compatibility.

In order to use AD the TCP/IP v4 protocol must be configured (both DNS and LDAP run over TCP/IP). While the Browser service also ran over IPX/SPX and the NetBIOS Frames Protocol (otherwise known as NBF or NetBEUI), this is not the case with AD.

Microsoft has produced a Knowledge Base Article that provides a list of Windows 2000 Domain Controller Default Ports. This provides an insight in to the protocols used with Active Directory.

The Knowledge Base Article is Q289241 and can be found at http://support.microsoft.com/default.aspx?scid=kb;en-us;289241

Domain Name System (DNS)

Active Directory requires a DNS infrastructure to be in place. AD does require that the DNS support dynamic updates, but uses the standard DNS. Thus in order to understand the impact of Active Directory on a network, it is necessary to understand the impact of DNS.

Some relevant RFCs are given below: