Hi sergii i have some working knowledge of ldap not much though but I think following your post, it will be great for MariaDb to incorporate an ldap plugin that could be used by organisations running ldap servers and  mariadb. For example most large organisations like Google keep information about their workers in a directory service on the servers. Creating users tables to hold this info will take too much time. Managing this table is also a huge task which can also reduce performance due to overpopulation. The ldap plugin will serve as an interface between mariadb and the directory service such that info can be retrieved with ease.

The cool stuff with ldap is that if a request is made to the directory service and the requested data is not there, a reference to another directory service that contains it is returned. The Ldap plugin if incorporated into mariadb can be used to authenticate users since in runs directly on the TCT/IP stack.

Please request for more details  if you need more explanation that will convince mariadb developpers to include this task at GSoc 2015.

 Best regards 

Chick