The ABCs of LDAP: How to Install, Run, and Administer LDAP Services

We have seen that a directory is a hierarchical repository of objects. A specialized agent, the directory server provides access to the directory. The objects in the directory are organized to optimize fast access.

Directory access protocols are used to provide directory services in a networked environment. The first commonly used directory access protocol (DAP) was the X.500 standard, a very powerful and complete protocol based on the OSI protocol stack. This DAP protocol offered many advantages and a very rich set of features. However, this feature-rich protocol is too heavy for use on personal computers, and it requires the resource-consuming OSI protocol stack. Consequently, a new protocol was developed to run over the TCP/IP protocol stack. Because this protocol leaves out the less commonly used features of DAP, it is called Lightweight Directory Access Protocol (LDAP). The less-resource-consuming LDAP protocol has had much greater acceptance than X.500. At the time of this writing, it is still a work in progress, although it is used in a production environment.

This chapter introduced the concept of LDAP and examined rudimentary applications. Chapter 2 extends the discussion, focusing on how to use an LDAP installation, how to get data in, how to define queries, how to make updates, and how to delete data. You will see the command-line utilities as well as the import and export possibilities LDAP offers. You will also learn about the LDIF (LDAP data interchange format) format that is produced by the export utilities.