Date: 29 Jul 1996 22:44:11 -0000
Message-ID: <19960729224411.26935.qmail@koobera.math.uic.edu>
From: djb@koobera.math.uic.edu (D. J. Bernstein)
To: drums@cs.utk.edu
Subject: Re: ``with foo'' legal?

> The list of known "via" and  "with"  values  are  registered
> with  the  Network  Information  Center, SRI International, Menlo
> Park, California.

Known doesn't mean legal. The 821 syntax refers to NIC, but the 822
syntax allows any atom.

I agree that it'd be good to (re-)encourage registration and
documentation of WITH values, so that Received lines become more useful
for their intended readers, but we also have to make clear when it's
okay to use an unregistered name.

(This is an immediate problem for me. I've implemented a QMTP server,
and I'd like to use ``with QMTP'' in the Received line.)

> via <mailername>

Also via <modulename>, such as CMU's ``via qmail'' or sendmail's ``with
internal''.

I don't see the line between the meaning of ``with'' and the meaning of
``via''. Current networks have far more than two layers:

   via SILVERSTREAK with ETHERNET with IP with TCP with SMTP

---Dan