directory service

database, networking A structured repository of information

on people and resources within an organisation, facilitating

management and communication.

On a LAN or WAN the directory service identifies all

aspects of the network including users, software, hardware,

and the various rights and policies assigned to each. As a

result applications can access information without knowing

where a particular resource is physically located, and users

interact oblivious to the network topology and protocols.

To allow heterogeneous networks to share directory

information the ITU proposed a common structure called

X.500. However, its complexity and lack of seamless

Internet support led to the development of LightweightDirectory Access Protocol (LDAP) which has continued to

evolve under the aegis of the IETF. Despite its name LDAP

is too closely linked to X.500 to be "lightweight".

LDAP was adopted by several companies such as NetscapeCommunications Corporation (Netscape Directory Server) and

has become a de facto standard for directory services.

Other LDAP compatible offerings include Novell, Inc.'s

Novell Directory Services (NDS) and MicrosoftCorporation's Active Directory. The Netscape and Novell

products are available for Windows NT and Unix

platforms. Novell Directory Services also run on Novell

platforms. Microsoft Corporation's Active Directory is an

integral part of Microsoft's Windows 2000 and although it

can interface with directory services running on other systems

it is not available for other platforms.

(2001-01-02)