The Most Complete History of Directory Services You Will Ever Find

I started working with Directory Servers back in 1997 when Netscape was but a fledging company. Over the past 15 years a lot has changed. Companies have come and gone and code has changed hands more times than I care to remember. But one thing remains the same – that little effort started by Tim Howes, Mark Smith, and Gordon Good at the University of Michigan is as important today as it was almost two decades ago.
I thought it might be worthwhile to take a look back at the various companies that have carried the LDAP mantle for stand-alone directory servers and see where we are today. As such, I have created a table of pertinent events (see below) as well as a graphical timeline (see thumbnail).
I offer you the industry’s most most complete history of directory services that you will ever find – well, at least until the next one comes along.

Directory Services Timeline

The Most Complete History of Directory Services You Will Ever Find

(Until the next one comes along)

Date Event


1969 First Arpanet node comes online; first RFC published.


1973 Ethernet invented by Xerox PARC researchers.


1982 TCP/IP replaces older Arpanet protocols on the Internet.


1982 First distributed computing research paper on Grapevine published by Xerox PARC researchers.


1984 Internet DNS comes online.


1986 IETF formally chartered.


1989 Quipu (X.500 software package) released.


1990 Estimated number of Internet hosts exceeds 250,000.


1990 First version of the X.500 standard published.


1991 A team at CERN headed by Tim Berners-Lee releases the first World Wide Web software.


1992 University of Michigan developers release the first LDAP software.


1993 NDS debuts in Netware 4.0.


July 1993 LDAP specification first published as RFC 1487.


December 1995 First standalone LDAP server (SLAPD) ships as part of U-M LDAP 3.2 release.


April 1996 Consortium of more than 40 leading software vendors endorses LDAP as the Internet directory service protocol of choice.


1996 Netscape Hires Tim Howes, Mark Smith, and Gordon Good from University of Michigan.  Howes serves as a directory server architect.


September 1997 Sun Microsystems releases Sun Directory Services 1.0, derived from U-M LDAP 3.2


November 1997 LDAPv3 named the winner of the PC Magazine Award for Technical Excellence.


December 1997 LDAPv3 approved as a proposed Internet Standard.


1998 The OpenLDAP Project was started by Kurt Zeilenga.  The project started by cloning the LDAP reference source from the University Of Michigan.


January 1998 Netscape ships the first commercial LDAPv3 directory server.


March 1998 Innosoft acquires Mark Walh’s Critical Angle company, relesases LDAP directory server product 4.1 one month later.


July 1998 Sun Microsystems ships Sun Directory Server 3.1, implementing LDAPv3 standards


July 1998 Estimated number of Internet hosts exceeds 36 million.


1999 AOL acquires Netscape and forms the iPlanet Alliance with Sun Microsystems.


March 1999 Innosoft team, led by Mark Wahl, releases Innosoft Distributed Directory Server 5.0


March 2000 Sun Microsystems acquires Innosoft, merges Innosoft directory code with iPlanet.  This forms the foundation for the iPlanet Directory Access Router.


October 2001 The iPlanet Alliance ends and Sun and Netscape fork the codebase.


October 2004 Apache Directory Server Top Level Project is formed after 1 year in incubation


December 2004 RedHat Purchases Netscape Server products


2005 Sun Microsystems initiates the OpenDS project.  An open source directory server based on the Java platform.


June 2005 RedHat Releases Fedora Directory Server


October 2006 Apache Directory Server 1.0 is released


2007 UnboundID releases its directory server


2008 AOL Stops Supporting Netscape Products


April 2009 Oracle purchases Sun Microsystems


May 2009 RedHat changes the Fedora Directory Server to 389 Directory Server


Feb 1, 2010 ForgeRock is founded


Dec 2010 ForgeRock releases OpenDJ


July 2011 Oracle releases Oracle Unified Directory



(1) Understanding and Deploying LDAP Directory Services; Second Edition; Timothy A. Howes, Ph.D., Mark C. Smith, and Gordon S. Good.
(2) 389 Directory Server; History (
(3) Email exchange with Ludovic Poitou (ForgeRock).
(4) Press Release, March 16th, 1998; “Innosoft Acquires LDAP Technology Leader Critical Angle Inc. (
(5) OpenLDAP; Wikipedia (
(6) iPlanet; Wikipedia (
(7) OpenDS; Wikipedia (
(8) Netscape; Wikipedia (
(9) Press Release, April 20th, 2000; “Oracle Buys Sun” (
(10) 389 Directory Server; 389 Change FAQ (
(11) OpenDJ; Wikipedia (
(12)  Email exchange with Nick Crown (UnboundID).
(13) Press Release, July 20th, 2011; “Oracle Announces Oracle Unified Directory 11g” (

  • bcarlier April 17, 2012

    Nice. What about Novell or Microsoft directories?

    • idmdude April 17, 2012

      I acknowledge that Novell and Microsoft have both contributed to the directory services landscape in a big way. My intention on building this timeline, however, was to focus on stand-alone native LDAP servers. Novell and Microsoft have both been intentionally omitted as they could be considered more OS-based directory servers.

      • I beg to differ. Novell has long had distributions of eDirectory as stand alone LDAP servers on many platforms, including, Solaris, IBM AIX, HP-UX, Linux and Windows since 1999.

  • Hi !

    FYI, ApacheDS was really started in 2002, but at this time, it was hosted at Sourceforge, under another name : ldapd. Alex Karasulu was the one who initiated the whole effort. (

    Great post, btw !

  • idmdude April 17, 2012

    I have updated the diagram and timeline to recognize the UnboundID directory server. This was released in 2007 as a branch off of the OpenDS code base.

  • Even if AD is not a standalone LDAP server, at least AD/AM should be added to this list. Ok, it’s far from beng LDAP compliant, but still…

  • arnaud April 17, 2012

    what about these?
    – Siemens DirX
    – Nokia OneNDS
    – Alcatel-Lucent 8661
    – IBM RACF
    – OpenWave Directory
    – IBM Tivoli Directory Server (ITDS)
    – and don’t forget that at IBM, Lotus Domino had a Directory offering as well.

    I’m sure I am forgetting a bunch but my point is that the Directory space isn’t quite as inbred as this timeline suggests.

  • Manuel Juarez April 17, 2012

    Great post. What about Tivoli? and OID?

  • Brad Diggs April 17, 2012

    Hi Bill,

    You are off to a good start but have quite a ways to go. Like the Unix family tree, LDAP has quite an extensive history as well. I wish that I had time to incorporate some of the innovations introduced at each version but for now these version histories provide a good time line for their evolution.

    Here is the high level Sun/iPlanet/Java System/Enterprise Edition Directory Server history:
    * iPlanet Directory Server 4.0 – December, 1999
    * iPlanet Directory Server 4.1 – January, 2000
    * iPlanet Directory Server 4.11 – February, 2000
    * iPlanet Directory Server 4.12 – June, 2000
    * iPlanet Directory Server 4.13 – February, 2001
    * iPlanet Directory Server 4.15 – July, 2001
    * iPlanet Directory Server 4.16 – March, 2002
    * iPlanet Directory Server 5.0 – April, 2001
    * iPlanet Directory Server 5.1 – December, 2001
    * Directory Server Access Management Edition 5.0 – April, 2002
    * Directory Server Access Management Edition 5.1 – June, 2002
    * Sun Open Net Environment (ONE) Directory Server 5.1 – June, 2002
    * Sun Java System Directory Server 5.2 2004Q2 – November, 2004
    * Sun Open Net Environment (ONE) Directory Server 5.2 – January, 2005
    * Sun Java System Directory Server 5.2 2005Q1 – February, 2005
    * Sun Java System Directory Server 5.2 2005Q4 – September, 2005
    * Sun Java System Directory Server Enterprise Edition (6.0) – March, 2007
    * Sun Java System Directory Server Enterprise Edition (6.1) – June, 2007
    * Sun Java System Directory Server Enterprise Edition (6.2) – September, 2007
    * Sun Java System Directory Server Enterprise Edition (6.3) – April, 2008
    * Sun Directory Server Enterprise Edition (7.0) – November, 2009
    * Oracle Directory Server Enterprise Edition (11gR1) – August, 2010
    * Oracle Directory Server Enterprise Edition (11gR1PS1) – May, 2011

    Sun’s documentation for all above versions are available at:

    Here is Oracle Internet Directory Server’s version history as well:
    1.0 – Dec 1997
    2.0.4 – Oct 1999
    3.0.1 – Feb 2003
    9.0.4 – Mar 2004 – Nov 2005 – Aug 2006 – Sep 2007 – Dec 2008 (11g R1) – Jul 2009 (11g R1 PS 1) – Sep 2009 (11g R1 PS 2) – Apr 2010 (11g R1 PS 3) – Jan 2011 (11g R1 PS4) – May 2011 (11g R1 PS5) – Feb 2012

    Lastly, there are other directory servers that you may want to graft into your DIT as well.
    * Computer Associates directory
    * Openwave (formerly,, Unwired Planet, and Libris, Inc)
    * IBM Directory Server
    * SymLabs proxy
    * Radiant Logic proxy



  • Matt Ruane May 1, 2012

    Can’t be complete without Novell eDirectory. I know it started as an OS directory service, but it is also a fantastic LDAP directory, very easy to install and configure and the same directory install can be used as an LDAP or an OS directory service. Also can be installed on Windows, many flavours Unix and Linux.

  • Colin Robbins October 5, 2014

    Your readers may be interested in the sequence of events that led to the development of LDAP, based around work on DIXIE and UMich and DASED at UCL/PSI.

    These developments are described in the following blog article.

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