Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!think.com!barmar
From: barmar@think.com (Barry Margolin)
Newsgroups: comp.mail.misc
Subject: Re: Procedure for adding headers?
Message-ID: <1990Nov21.003144.4755@Think.COM>
Date: 21 Nov 90 00:31:44 GMT
References: <16502@csli.Stanford.EDU>
Sender: news@Think.COM
Organization: Thinking Machines Corporation, Cambridge MA, USA
Lines: 39

In article <16502@csli.Stanford.EDU> dmr@csli.Stanford.EDU (Daniel M. Rosenberg) writes:
>Who maintains the set of standards for mail headers (like From: and
>>Path: and whatever). Is it just sort of my mutual agreement of
>people who write routers and mailers and readers?

The format of mail on the Internet is specified by a document known as
RFC-822, which can be accessed via anonymous FTP from NIC.DDN.MIL with the
file name "RFC:RFC822.TXT".  Internet standards are currently specified by
the Internet Activities Board and the Internet Engineering Task Force,
which I believe are supported by DARPA (there's an RFC that describes the
charters of these organizations -- look it up in RFC:RFC-INDEX.TXT).

>And has anyone thought of adding a Priority: {High, Middle, Low} to
>the list, with Low messages being the Madonna mailing list; Middle
>being regularly scheduled meetings; High being time-sensitive, more
>urgent information (and so forth)?

Adding a header field is almost certainly not enough.  Mail transfer
programs generally are not required to look at the header of the messages
they are transfering.  In the Internet SMTP protocol, all the information
needed to deliver mail is provided separately as commands issued to the
server (this allows messages to be delivered to addresses not mentioned
explicitly in the header, e.g. for blind carbon copies or mailing list
explosion).  Priority would have to be specified externally in this manner.
Other mail systems (such as the CCITT X.400 protocols) similarly provide a
distinction between header attributes (intended for the recipient) and
envelope attributes (used by the mail software).

In fact, the CCITT X.400 envelope specification includes such an option.
One word of warning, though: what prevents someone from being obnoxious and
sending high priority mail to the Madonna mailing list?  And if we were to
extend SMTP to support such an option, what should happen if high priority
mail has to go through a system that hasn't yet implemented the option?

--
Barry Margolin, Thinking Machines Corp.

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