Some how related to the Red Hat Directory Server which is a commercial product with support.
In 1996 the original developers of SLAPD became Netscape employees and developed Netscape Directory Server, was renamed to Fedora Directory Server when purchased by RedHat in 2004 and then later renamed to 389 Directory Server
The two projects have a lot in common: support for LDAPv3 including:
- many of the most commonly used controls and extensions;
- high performance (with the latest revisions of OpenLDAP 2.2.x/2.3 and BerkeleyDB 4.2.x/4.3),
- some form of replication,
- multiple back-end support,
- access control,
- and others.