Based on the Lightweight Directory Access Protocol (LDAP), the 389 Directory Server is designed to manage large directories of users and resources robustly and scalably.

Its key features include: * four-way multi-master replication; * great scalability; * extensive documentation; * Active Directory user and group synchronization; * secure authentication and transport; * support for LDAPv3; * graphical management console; * on-line, zero downtime update of schema, configuration, and in-tree Access Control Information.