What Is the Lightweight Directory Access Protocol (LDAP)?
LDAP is a standard, extensible directory access protocol. It is a common language that LDAP clients and servers use to communicate.
This section contains these topics:
LDAP and Simplified Directory Management
LDAP was conceived as an Internet-ready, lightweight implementation of the International Standardization Organization (ISO) X.500 standard for directory services. It requires a minimal amount of networking software on the client side, which makes it particularly attractive for Internet-based, thin client applications.
The LDAP standard simplifies management of directory information in three ways:
- It provides all users and applications in the enterprise with a single, well-defined, standard interface to a single, extensible directory service. This makes it easier to rapidly develop and deploy directory-enabled applications.
- It reduces the need to enter and coordinate redundant information in multiple services scattered across the enterprise.
- Its well-defined protocol and array of programmatic interfaces make it more practical to deploy Internet-ready applications that leverage the directory.
LDAP Version 3
The most recent version of LDAP, Version 3, was approved as a proposed Internet Standard by the Internet Engineering Task Force (IETF) in December 1997. LDAP Version 3 improves on LDAP Version 2 in several important areas:
- Globalization Support: LDAP Version 3 allows servers and clients to support characters used in every language in the world.
- Knowledge references (also called referrals): LDAP Version 3 implements a referral mechanism that allows servers to return references to other servers as a result of a directory query. This makes it possible to distribute directories globally by partitioning a directory information tree (DIT) across multiple LDAP servers.
- Security: LDAP Version 3 adds a standard mechanism for supporting Simple Authentication and Security Layer (SASL), providing a comprehensive and extensible framework for data security.
- Extensibility: LDAP Version 3 enables vendors to extend existing LDAP operations through the use of mechanisms called controls.
- Feature and schema discovery: LDAP Version 3 enables publishing information useful to other LDAP servers and clients, such as the supported LDAP protocols and a description of the directory schema.
