資料來源 : Free On-Line Dictionary of Computing
directory service
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 {Lightweight
Directory 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 {Netscape
Communications 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 {Microsoft
Corporation}'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)