LDAP is a short hand for Light weight Directory Access Protocol. It is a standard protocol used by the application to access the information in a directory. It runs over TCP and can used a standalone LDAP directory service which has a backend X.500.
The LDAP service model is based on the number of Entries. An entry is a collection of the attributes which describes it. Each attribute has unique characteristics which contains name, type and many more.
A LDAP directory tree often reflects geographic and organization concerns. In LDAP directories the entries are arranged in tree structure, which starts at root and goes till leaf. At the top level it represents the larger organizations. This larger directories contains smaller organization. Each entry has a distinguished name. The DN(Distinguished Name) consists of unique and a path of the names that trace till the root.
LDAP is based on Client – server model. In which the LDAP server provides the directory service while the clients use the directory service to access the directory.
Some of the operations of the LDAP directories.
1. Search and Retrieve the entries.
2. Updating the entries.
3. Renaming , adding and deleting the entries.
To perform the operations the client has to establish the connection with the server. It uses the TCP/IP and port no 389 (sever can run on different ports). It has a very simplified authentication process.