- [389 Directory Server](http://www.port389.org/) - Developed by Red Hat.
- [Apache Directory Server](http://directory.apache.org/) - Apache Software Foundation project written in Java.
- [FreeIPA](http://www.freeipa.org/) - Based on 389-DS. Includes Kerberos, DNS, as well as host based access control.
- [FreeRADIUS](http://freeradius.org/) - High performance and highly configurable multi-protocol policy/authentication server, supporting RADIUS, DHCPv4 and VMPS.
- [389 Directory Server](https://www.port389.org/) - Enterprise-class Open Source LDAP server for Linux.
- [Apache Directory Server](https://directory.apache.org/apacheds/) - Extensible and embeddable directory server, certified LDAPv3 compatible, with Kerberos 5 and Change Password Protocol support, triggers, stored procedures, queues and views. `Java`
- [FreeIPA](https://www.freeipa.org/) - Integrated security information management solution combining Linux (Fedora), 389 Directory Server, Kerberos, NTP, DNS, and Dogtag Certificate System (web interface and command-line administration tools).
- [FreeRADIUS](https://freeradius.org/) - Multi-protocol policy server (radiusd) that implements RADIUS, DHCP, BFD, and ARP and associated client/PAM library/Apache module.
- [lldap](https://github.com/nitnelave/lldap) - Light (simplified) LDAP implementation with a simple, intuitive web interface and GraphQL support. `GPL-3.0``Rust`
- [lldap](https://github.com/nitnelave/lldap) - Light (simplified) LDAP implementation with a simple, intuitive web interface and GraphQL support. `GPL-3.0``Rust`
- [OpenDJ](http://opendj.forgerock.org/) - Fork of OpenDS.
- [OpenDJ](http://opendj.forgerock.org/) - Fork of OpenDS.
- [OpenDS](https://opends.java.net/) - Another directory server written in Java.
- [OpenDS](https://opends.java.net/) - Another directory server written in Java.