Introduction To Directory Server - Red Hat DIRECTORY SERVER 8.1 - DEPLOYMENT Deployment Manual

Chapter 1. Introduction to Directory Services
increased hardware and personnel costs; the increased maintenance overhead is referred to as the n
+1 directory problem.
A global directory service solves the n+1 directory problem by providing a single, centralized
repository of directory information that any application can access. However, giving a wide variety
of applications access to the directory service requires a network-based means of communicating
between the applications and the directory service. Directory Server uses LDAP for applications to
access to its global directory service.
1.1.2. About LDAP
LDAP provides a common language that client applications and servers use to communicate with one
another. LDAP is a "lightweight" version of the Directory Access Protocol (DAP) described by the ISO
X.500 standard. DAP gives any application access to the directory through an extensible and robust
information framework but at a high administrative cost. DAP uses a communications layer that is not
the Internet standard protocol and has complex directory-naming conventions.
LDAP preserves the best features of DAP while reducing administrative costs. LDAP uses an open
directory access protocol running over TCP/IP and simplified encoding methods. It retains the
data model and can support millions of entries for a modest investment in hardware and network
infrastructure.

1.2. Introduction to Directory Server

Red Hat Directory Server includes the directory itself, the server-side software that implements the
LDAP protocol, and a client-side graphical user interface that allows end-users to search and change
entries in the directory. Other LDAP clients, both third-party programs and custom programs written
using the LDAP client SDK, both the Mozilla LDAP SDK and the OpenLDAP SDK.
Without adding other LDAP client programs, Directory Server can provide the foundation for an
intranet or extranet. Every Directory Server and compatible server applications use the directory as
a central repository for shared server information, such as employee, customer, supplier, and partner
data.
Directory Server can manage user authentication, create access control, set up user preferences, and
centralize user management. In hosted environments, partners, customers, and suppliers can manage
their own portions of the directory, reducing administrative costs.
When Directory Server is installed and set up, the following components are installed:
• The core Directory Server LDAP server, the LDAP v3-compliant network daemon (ns-slapd) and
all of the associated plug-ins, command-line tools for managing the server and its databases, and
its configuration and schema files. For more information about the command-line tools, see the
Directory Server Configuration, Command, and File Reference.
• Administration Server, a web server which controls the different portals that access the LDAP
server. For more information about the Administration Server, see Using the Admin Server.
• Directory Server Console, a graphical management console that dramatically reduces the effort of
setting up and maintaining the directory service. For more information about the Directory Server
Console, see Using Red Hat Console.
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