Re: x.400 protocol implementation
Thursday, May 5, 2005 05:51 PM
Yuck, you have my utmost sympathies...
Fortunately I think now just about every one of the handful of features that was at all desirable about X.400 can now be done, in standard ways, on top of good ole Internet (SMTP-based) mail.
Especially with LDAP now able to replace the nightmare that was X.500/DAP (which was the OSI's, hence X.400's, monstrous impossible addressing and directory interface).
Also especially since the whole world has basically admitted that IP/TCP/UDP rules, as the network transport of choice, and OSI networking (hence X.400) things, like ATM and all its predecessors (X.25, TP0-TP3, etc.) totally sucked. (the Europeans even admitted defeat and defined "TP4", and "CLNP", which were just TCP and IP renamed, so you could pretend you were using their system, even though you really were just using good old TCP/IP!)
Read Marshall Rose's "The Open Book", if you don't believe me ... OSI, hence X.400 etc., was all invented by European telephony monopoly beaureaucrats, who were upset that the Internet protocols (IP/TCP etc.), originally funded by the US. Defense Dept., were on the verge of taking over the world. They wanted a European alternative.
Unfortunately their design only worked on paper, in theory. You would get email systems where you could only send email to someone inside the same system (e.g. under the same X.500 directory root, "AN" "Administrative Name", "PN" "Provider Name"? etc.).
Other email systems (under other "AN"/"PN" directory roots, or even with the same "AN" but different "OU" Org Names) were completely unreachable. It was the European national telephony monopolies' version of messaging -- you could only message other customers of the same national company, e.g. "PN"/"AN"! The whole "Inter" part of the "Internet" was omitted, from OSI/X.400 etc., by intentional design.
Equally unfortunately, the U.S. Government was snowed by them, for a couple of years, into issuing the "GOSIP", which mandated that all US Government contractors etc. use OSI protocols (e.g. X.400 etc.).... that's the only reason that any X.400 implementations saw the light of day, even though they all sucked ... because you needed one to do business with the U.S. Government those dark years! Fortunately the GOSIP was rescinded, replaced entirely, just a few years later, and now as far as I know, the US Government requirements are all entirely Internet, IP/TCP based (including SMTP for email).
Compromises came out, like LDAP (over TCP/IP), replacing the awful DAP (Directory Addressing Protocol) of X.500, over OSI networking protocols. This and other standards, developed on the Internet side, made it possible for SMTP based Internet email systems to send and receive mail to X.400 systems through "gateways".
Lotus Notes mail server is/was based on X.400, because it was designed around that time of the GOSIP. Don't know about Domino now. So I would check IBM's web sites, for Lotus, and Developer Zones, Alphaworks, etc.
Old Microsoft Exchange Server (v4 maybe? the one that originally came with NT 4 Server) also used to be based on X.400 internally (and hence was nearly impossible to understand), since it was designed around that time of the GOSIP too. Can you say "MAPI"? though MAPI and the predecessor of Exchange+Outlook, "Microsoft Mail", actually predated X.400 ...
I think the current MS Exchange Server is based on on just Internet protocols (SMTP, LDAP etc.) now? and MAPI etc. are just a thin emulation layer, with no more X.400 or X.500 crap underneath? but I could be wrong about this.
I worked for Siemens Corp. years ago during this GOSIP X.400 manic phase and we unfortunately had to learn how to interoperate with some X.400 "gateways" (basically "manglers" of messages....).... so check siemens.com.
Some German Siemens companies had an X.500 implementation and an LDAP client interface to it, which we had to install at one point, maybe called "XDIR"? I forget, it was almost 10 years ago...