Date: Tue, 3 Oct 95 20:31:09 -0500
From: Eric Norman <ejnorman@macc.wisc.edu>
Reply-To: drums@CS.UTK.EDU
Message-Id: <9510040131.AA13308@dogie.macc.wisc.edu>
To: drums@CS.UTK.EDU
Subject: Re: What's the Sender header for?

> Basically, the question amounts to whether mailing lists should be 
> munging the Sender field.  (At least, I don't know of any other 
> controversy regarding this field.)

I don't know whether they should or not, but I think they may

       *as long as they munge in the right address*.

For example, we have this list that's known as drums@cs.utk.edu.
Suppose someone is going to insert a Sender: header that identifies
the AGENT (person, system, or process) that caused the message to
be sent.  Who or what causes the message to be sent to all those
folks?  The right answer is drums-request@cs.utk.edu; that's the
agent that put my name on the mailing list; that's the agent that
caused the message to be sent to me; that's the agent that I talk
to if I don't want any more such messages.

There's no implication that drums-request@cs.utk.edu is a human
being; it may indeed be a system (e.g. SmartList, listproc, etc).

The address drums@cs.utk.edu represents a whole collection of fine,
upstanding, folks.  This whole collection *does not* cause a message
to be sent to me or to anyone else.  Ergo, a Sender: header that
addresses this whole collection doesn't make much sense.  Furthermore,
RFC822 specifically says (4.4.4) that the Sender: field should be
sent notices of non-delivery, etc.  It's not clear, but I suppose
this would only apply in a non-SMTP environment without envelope
return addresses (yes, I know Return-Path: would be better too in
such an environment).  However, that fact remains that RFC822 *does*
say that error notices may (should) be sent to the Sender: address,
so aiming this back at the whole list would be asking for big trouble.

> I personally feel that Sender should identify the original human
> sender, and that mailing lists shouldn't change it.  For them to
> do so removes the ability of a list recipient to see who actually
> sent the message.  

In almost all cases, the original human sender is identified by the
From: header.  In all cases, this MUST identify who authored the
message.  Is that what you mean by the verb "send"?

-- Eric Norman