LDAP
Lightweight Directory Access Protocol. A protocol for accessing online
directory services via Web browsers and e-mail programs that are LDAP-compliant. Some
expect that LDAP will provide a common method for searching e-mail addresses on
the Internet, eventually leading to a global white pages.
LDAP was defined by the Internet Engineering Task Force (IETF) to encourage adoption of X.500 directories. LDAP is a relatively simple
protocol for updating and searching directories running over TCP/IP. Its predecessor, the Directory Access Protocol (DAP), was seen as too
complex for simple Internet clients to use.
An LDAP directory entry is a collection of attributes with a name, called a
distinguished name (DN). The DN refers to the entry unambiguously. Each of the
entryÆs attributes has a type and one or more values. The types are typically
mnemonic strings, like ôcnö for common name, or ômailö for e-mail address. The values depend on the type.
LDAP directory entries are arranged in a hierarchical structure that reflects
political, geographic, and/or organizational boundaries. Entries representing
countries appear at the top of the tree, followed by entries representing states
or national organizations that are followed by entries representing people,
organizational units, printers, documents, etc.