LDAP Lightweight Directory Access Protocol is a protocol for networked directories [L1 ].
There are four independent (?) implementations, ldapTcl, Matt Newman's LDAP extension [L2 ], Jochen Loewer's (see below), a derivative of the latter available in tcllib as of 2004, and Gareth Owen's tclLdap-pkg [L3 ] (but is this a derivative of an early tclLdap?). It would be particularly useful to compare the latter two.
I did a pure Tcl implementation of a ldap interface in June 99. See (Jochen Loewer). It is running since then very nicely to query a large enterprise wide people directory. Right now only the read/query parts of the protocol are implemented. However, the internal ASN layer is there, so it should be rather easy to extend it. Unfortunately I didn't release the code to the public yet. I thought about that several times. It would be ideal for tcllib or even standard tcl (like the http package). CL: ooooo. ASN.1 would be nice for tcllib.
ak: Tcllib head provides an (incomplete) asn package. Directly derived from the code in the ldap package.
Interesting LDAP-based applications include Owen's Ldapper [L4 ] (which pages says it was last modified Wed Feb 3 17:46:54 GMT 1999).
As of 2004, the major category of LDAP servers are instances of Microsoft's Active Directory.
CL observes that learning to work with LDAP can intimidate newcomers, if only for the usual complication of client-server protocols (SNMP presents the same challenge): one must have a working server and client before achieving the "Hello, world" level of progress. In the '90s, there were quite a few public LDAP services, and it was inviting to connect new client applications to them for quick exercise. As far as I know, they're all gone now [task: confirm this]. Is there interest in Tclistan for a public LDAP server against which we can all practice? I might set one up ... (again, same's true for SNMP).
Patrick Finnegan provided several IBM-pertinent example LDAP-using scripts [L5 ] to the Cookbook.