LDAP - Lightweight Directory Access Protocol, Basics

In every distributed system with many users and centralized user management, there is need for database which will contain base informations on every user. This database in Microsoft environment is known as Active Directory (most common choice) and in UNIX environment that database is called LDAP or Lightweight Directory Access Protocol.

LDAP is application part protocol for accessing and maintaining distributed directory information services over IP network. Let's stop for a second and think about Directory services. If you don't know what it is, we will tell you in the moment.

Lets put it in the simple words, directory service is public available database of hierarchicaly structured informations. Everyone are using analogy with Yellow pages, so we are going to do the same. When you open Yellow pages you see names, addresses, contact numbers of various businesses, structured and indexed by category to be easily browseable. So in some company LDAP can contain names, phone numbers, location, e-mail addresses, department and lot of other informations about employee.

LDAP allows easy and quick search of directory services, it makes possible to easily update and query directory services over TCP/IP. TCP/IP? Yes, exactly, LDAP is based on client-server model in which your environment can contain one, two or more LDAP servers, multiple clients. Most common usage of LDAP directories in corporate networks is for corporate address books applications and e-mail clients, such as MS Outlook, Eudora or Thunderbird.

In next part of tutorial we will see how LDAP model and structure look like.