Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!think!barmar
From: barmar@think.COM (Barry Margolin)
Newsgroups: comp.misc
Subject: Re: Standardizing Email?
Message-ID: <26196@think.UUCP>
Date: 22 Aug 88 20:37:32 GMT
References: <788@vsi.UUCP> <79700010@p.cs.uiuc.edu> <304@pvab.UUCP>
Sender: usenet@think.UUCP
Reply-To: barmar@kulla.think.com.UUCP (Barry Margolin)
Organization: Thinking Machines Corporation, Cambridge, MA
Lines: 34

In article <304@pvab.UUCP> robert@pvab.UUCP (Robert Claeson) writes:
>What does an X.400 address look like?

If you're asking what the equivalent to user@domain and
host!host!...!user is, there isn't really such a thing, since X.400 is
not a textual protocol.  Both messages and the the message-transfer
protocol are binary, based on structured objects.  There are a variety
of forms of Originator/Recipient Names (O/R Names), which might need
to be used in combination in order to uniquely designate a recipient.
For example, one of the formats is simply the recipient's personal
name (structured into Surname, Given name, Initials, Generational
qualifier), but you'd probably need to augment it with other
information, such as geographical or organizational info.  The intent
is to eventually allow you to address electronic mail the same way you
would address postal mail; a complicated distributed database (which
is in the early design stage, I think) would figure out how to get it
to the right electronic mailbox.  There are, of course, O/R Name
formats that specify specific hosts (using X.121 addresses, for
example) and users on that system.

Since all communication is in the form of structured objects, there
won't be any ambiguous addresses.  For example, on a host that
implements both UUCP and Internet mail, the address host!user@domain
is ambigous (it could mean either (host!user)@domain or
host!(user@domain)), but this form of ambiguity is not possible in
X.400 because there is no parsing involved (except, perhaps, by the
user application used to create mail, but that's not the problem of
the mail transfer protocol).


Barry Margolin
Thinking Machines Corp.

barmar@think.com
{uunet,harvard}!think!barmar