Subject: Re: Getting the DSN standard used
From: "Jack De Winter" <[email-masked]>
To: Tim Showalter <[email-masked]>, [email-masked]
Date: Fri, 29 May 1998 13:43:42 -0400

>Dan's link works in Netscape 2 (Solaris), Netscape 3 (Linux), Netscape 4
>(Linux), and Lynx (Linux).  It even worked in the circa 1993 CERN
>browser "www" (SunOS binary running under Solaris, although www makes
>you go through the FTP redirect by hand).
>
>I've had two problems with Dan's URLs: one, a URL posted to DRUMS in
>1996 is invalid; two, deleting the filename off of the URL (to hopefully 
>look at the list of documents in that directory) doesn't work as far as
>I know.  But these are my fault, and my problem, and do not interfere
>with chasing that link.
>
>Surprisingly, the link in your signature appears to be invalid in all of 
>the above browsers plus "telnet www.wildbear.on.ca 80".

Noted... moved stuff around on the web site, and thought I had updated
my links.

>Incidentially, what browser is preventing you from getting that link?

I have tried Netscape 2, 3 and 4, IE 3 and 4, and the latest release
of Opera, all to no avail.  Each of them returns that the request was
illegal.

regards,
Jack
-------------------------------------------------
Jack De Winter - Wildbear Consulting, Inc.
(519) 884-4498		http://www.wildbear.on.ca/homepages/jack/

To: [email-masked]
Subject: Re: Getting the DSN standard used
From: Arnt Gulbrandsen <[email-masked]>
Date: 29 May 1998 16:22:28 +0200
Lines: 15
Sender: [email-masked]

Jacob Palme <[email-masked]>
> The most important part of the DSN standard is the standardized format
> for non-delivery DSNs.

Is it?  I am probably almost unique: I send NOTIFY=SUCCESS mail on a
regular basis (using some hacks of my own).  IMHO, the fact that I can
count on receiving either a 'delivered' or a 'relayed' DSN is the most
important feature in the long term.  The fact that its format is
parsable is the second most important part (insert minor sendmail
grumble here).

Having one widely available mail client that's able to list what
recipients have recived any send mail might help a lot.

--Arnt

Date: 28 May 1998 19:19:01 -0400
From: Tim Showalter <[email-masked]>
To: [email-masked]
Subject: Re: Getting the DSN standard used
Sender: [email-masked]

> Date: Thu, 28 May 1998 17:37:33 -0400
> From: "Jack De Winter" <[email-masked]>
> 
> >Those functions don't require DSN unless they're foolishly implemented.
> >See http://pobox.com/~djb/proto/verp.txt.
> 
> Please do not post URLs for sites that most of us cannot access.
> It is both infuriating and a pain.  Try doing something like posting
> the data here.
> [...]
> (519) 884-4498		http://www.wildbear.on.ca/jacks/

Dan's link works in Netscape 2 (Solaris), Netscape 3 (Linux), Netscape 4
(Linux), and Lynx (Linux).  It even worked in the circa 1993 CERN
browser "www" (SunOS binary running under Solaris, although www makes
you go through the FTP redirect by hand).

I've had two problems with Dan's URLs: one, a URL posted to DRUMS in
1996 is invalid; two, deleting the filename off of the URL (to hopefully 
look at the list of documents in that directory) doesn't work as far as
I know.  But these are my fault, and my problem, and do not interfere
with chasing that link.

Surprisingly, the link in your signature appears to be invalid in all of 
the above browsers plus "telnet www.wildbear.on.ca 80".

Incidentially, what browser is preventing you from getting that link?

-- 
Tim Showalter <[email-masked]>

Date: 28 May 1998 21:57:51 -0000
Mail-Followup-To: [email-masked]
From: "D. J. Bernstein" <[email-masked]>
To: [email-masked]
Subject: Re: Getting the DSN standard used
Sender: [email-masked]

Jack De Winter writes:
> Please do not post URLs for sites that most of us cannot access.

Your current browser has some serious bugs. Why don't you use Netscape?
Or lynx, if you need something that works with dumb terminals.

---Dan
50000 new aliases in 6 seconds. http://pobox.com/~djb/fastforward.html

Date: 28 May 1998 21:40:15 -0000
Mail-Followup-To: [email-masked]
From: "D. J. Bernstein" <[email-masked]>
To: [email-masked]
Subject: Re: Getting the DSN standard used
Sender: [email-masked]

Jacob Palme writes:
> (b) Mail clients can collect the DSNs, so that a user can give
>     a command asking which recipients for a particular message
>     have generated non-delivery DSNs.

Pay attention. The MUA can easily do this, 100% reliably, _without_ a
standardized bounce format. See http://pobox.com/~djb/proto/verp.txt.

> The most important part of the DSN standard is the standardized format
> for non-delivery DSNs.

How could it possibly be ``important'' to generate a format that is, as
a practical matter, understood by neither man nor machine? Extracting
useful information from DSN is a royal pain.

> To: "D. J. Bernstein" <[email-masked]>, [email-masked]

Please don't send me extra copies of your messages, Jacob.

---Dan
50000 new aliases in 6 seconds. http://pobox.com/~djb/fastforward.html

Date: Thu, 28 May 1998 17:37:33 -0400
To: "D. J. Bernstein" <[email-masked]>, [email-masked]
From: "Jack De Winter" <[email-masked]>
Subject: Re: Getting the DSN standard used
Sender: [email-masked]

At 04:07 PM 5/28/98 -0000, D. J. Bernstein wrote:
>Jacob Palme writes:
>> What can be done to get more support?
>
>Give up and start over. MUAs need something easy to parse; MTAs need
>something easy to generate; users need something that works end-to-end
>without link-level support.
>
>> Mail clients can support DSNs in several ways.
>
>Those functions don't require DSN unless they're foolishly implemented.
>See http://pobox.com/~djb/proto/verp.txt.

Please do not post URLs for sites that most of us cannot access.
It is both infuriating and a pain.  Try doing something like posting
the data here.

regards,
Jack
-------------------------------------------------
Jack De Winter - Wildbear Consulting, Inc.
(519) 884-4498		http://www.wildbear.on.ca/jacks/

Date: Thu, 28 May 1998 21:01:35 +0200
To: "D. J. Bernstein" <[email-masked]>, [email-masked]
From: Jacob Palme <[email-masked]>
Subject: Re: Getting the DSN standard used
Sender: [email-masked]

At 18.07 +0200 98-05-28, D. J. Bernstein wrote:
> Jacob Palme writes:
> > What can be done to get more support?
>
> Give up and start over. MUAs need something easy to parse; MTAs need
> something easy to generate; users need something that works end-to-end
> without link-level support.

The most important part of the DSN standard is the standardized format
for non-delivery DSNs. This can be supported *even* if you do not support
the ESMTP commands to control generation of DSNs.

The value with this standardized format is that

(a) Mail clients can display it in ways the user understands.

(b) Mail clients can collect the DSNs, so that a user can give
    a command asking which recipients for a particular message
    have generated non-delivery DSNs.

(c) Non-delivery DSNs can be filtered. In particular, if a user
    uses option (b), the user might prefer not to see the DSNs
    at all when they arrive.
------------------------------------------------------------------------
Jacob Palme <[email-masked]> (Stockholm University and KTH)
for more info see URL: http://www.dsv.su.se/~jpalme

Date: 28 May 1998 16:07:59 -0000
Mail-Followup-To: [email-masked]
From: "D. J. Bernstein" <[email-masked]>
To: [email-masked]
Subject: Re: Getting the DSN standard used
Sender: [email-masked]

Jacob Palme writes:
> What can be done to get more support?

Give up and start over. MUAs need something easy to parse; MTAs need
something easy to generate; users need something that works end-to-end
without link-level support.

> Mail clients can support DSNs in several ways.

Those functions don't require DSN unless they're foolishly implemented.
See http://pobox.com/~djb/proto/verp.txt.

---Dan
50000 new aliases in 6 seconds. http://pobox.com/~djb/fastforward.html

Comments: Authenticated sender is <[email-masked]>
From: "Rolf E. Sonneveld" <[email-masked]>
Organization: Sonnection
To: Keith Moore <[email-masked]>
Date: Wed, 27 May 1998 23:08:24 +0200
Subject: Re: Getting the DSN standard used 
Reply-to: [email-masked]
CC: [email-masked] (Jacob Palme), [email-masked]
Sender: [email-masked]

As a followup to Keith's message:

> > > The DSN standards (RFC 1891, 1892, 1894) have now been
> > > ready for more than two years. Yet very few mailers support
> > > them. What can be done to get more support?
> 
> First a response to Jacob's comment: Last time I went to an
> interoperability test, most major vendors of SMTP were supporting DSN.

> > I'm afraid there are two major obstacles to the widespread use of DSN:
> > 
> > 1. the amount of User Agents supporting DSN is low
> 
> Yes, but this only explains the inability to request delivery
> confirmation.  DSNs are very useful even if many clients don't support
> them.

When I wrote this I was thinking about the support in UA's for the 
proper and decent presentation of DSN 'compliant' messages/bodyparts. 
For most 'ordinary' non-technical users the three-part messages are 
still not very helpful in determining what's wrong or what's OK with 
the message they had sent. I think this is a similar problem to the 
problem with the deployment of MIME back in 1992, when MIME 
just was released. User Agents then presented the user with the raw 
MIME structure. Now most UA's present MIME format messages properly. 

> Note that there are two levels of support for DSN in MTAs:
> 
> 1. if they generate nondelivery reports in DSN format
> 2. if they advertise the DSN SMTP extension, implying that they 
>    support NOTIFY, ENVID, etc.
> 
> The first is easier to do than the second.  
> 
> 
> > 2. from my experience I know that in a significant number of cases
> >    the problem why DSN is not supported by a company e-mail infrastructure
> >    the firewall that's being used in the real world. In many cases the
> >    firewall has an active mail component, thus limiting the support for
> >    SMTP and extensions to what the firewall provides. And more often then
> >    not the firewall does not support DSN or does not even ESMTP at
> >    all!
> 
> Yes, firewalls are a major problem.
> 
> We need a clear community statement to the effect that firewalls that
> block arbitrary SMTP extensions are nonstandard and broken.

I support your statement here!

/rolf

--

Rolf E. Sonneveld

Sonnection
Schrijnwerkerlaan 16
3828 XC Hoogland
The Netherlands
Tel./Fax. +31 33 480 3968
Mobile:   +31 6543 70 20 5
E-mail: [email-masked]
Homepage: http://www.sonnection.nl

From: Keith Moore <[email-masked]>
To: "R.E. Sonneveld" <[email-masked]>
cc: [email-masked] (Jacob Palme), [email-masked], [email-masked]
Subject: Re: Getting the DSN standard used 
Date: Wed, 27 May 1998 15:10:47 -0400
Sender: [email-masked]

> > The DSN standards (RFC 1891, 1892, 1894) have now been
> > ready for more than two years. Yet very few mailers support
> > them. What can be done to get more support?

First a response to Jacob's comment: Last time I went to an
interoperability test, most major vendors of SMTP were supporting DSN.

> I'm afraid there are two major obstacles to the widespread use of DSN:
> 
> 1. the amount of User Agents supporting DSN is low

Yes, but this only explains the inability to request delivery
confirmation.  DSNs are very useful even if many clients don't support
them.

Note that there are two levels of support for DSN in MTAs:

1. if they generate nondelivery reports in DSN format
2. if they advertise the DSN SMTP extension, implying that they 
   support NOTIFY, ENVID, etc.

The first is easier to do than the second.  

> 2. from my experience I know that in a significant number of cases
>    the problem why DSN is not supported by a company e-mail infrastructure
>    the firewall that's being used in the real world. In many cases the
>    firewall has an active mail component, thus limiting the support for
>    SMTP and extensions to what the firewall provides. And more often then
>    not the firewall does not support DSN or does not even ESMTP at
>    all!

Yes, firewalls are a major problem.

We need a clear community statement to the effect that firewalls that
block arbitrary SMTP extensions are nonstandard and broken.

Keith

From: "R.E. Sonneveld" <[email-masked]>
Subject: Re: Getting the DSN standard used
To: [email-masked] (Jacob Palme)
Date: Tue, 26 May 1998 11:44:53 +0200 (MET DST)
Cc: [email-masked]
Sender: [email-masked]

Jacob,

> The DSN standards (RFC 1891, 1892, 1894) have now been
> ready for more than two years. Yet very few mailers support
> them. What can be done to get more support?

I'm afraid there are two major obstacles to the widespread use of DSN:

1. the amount of User Agents supporting DSN is low
2. from my experience I know that in a significant number of cases
   the problem why DSN is not supported by a company e-mail infrastructure
   the firewall that's being used in the real world. In many cases the
   firewall has an active mail component, thus limiting the support for
   SMTP and extensions to what the firewall provides. And more often then
   not the firewall does not support DSN or does not even ESMTP at all!
 
> Does sendmail produce DSN in the standardized format? If
> yes, how can we get people to update to a more recent
> version of sendmail. If not, how can we get it to support

I think Sendmail is not the problem. Due to Sendmail's security
problems, most customers have recent releases of Sendmail deployed.

> Mail clients can support DSNs in several ways. I list them
> below in my suggested priority order:
> 
> (1) Display standardised DSNs in a standard format, which
>     contains the information the user needs in easy to read
>     format.
> 
> (2) Allow filtering incoming DSNs to a special folder.
> 
> (3) A command to look at a sent message, and then get a
>     list of all delivery and receipt notifications for this
>     message, one line per note. Something like this:
> 
>         Received by: xxx
>         Received by: (printed on paper) yyy
>         Delivered to: zzz
>         Could not be delivered to: qqq
> 
>     This option is of course very useful in conjunction
>     with option (2).
> 
> (4) Commands to request delivery and receipt notifications
>     and to request supression of them.
> 
> Mail clients cannot be expected to support this until
> sendmail and other MTA software starts supporting them.

Yes, but I think in many cases the vendors of UA software should do more
to support DSN's and vendors of firewalls should get up to date with
their e-mail software.

Regards,

/rolf

Rolf E. Sonneveld
Sonnection
The Netherlands

Date: Tue, 26 May 1998 09:56:06 +0200
To: [email-masked]
From: Jacob Palme <[email-masked]>
Subject: Getting the DSN standard used
Sender: [email-masked]

The DSN standards (RFC 1891, 1892, 1894) have now been
ready for more than two years. Yet very few mailers support
them. What can be done to get more support?

Does sendmail produce DSN in the standardized format? If
yes, how can we get people to update to a more recent
version of sendmail. If not, how can we get it to support
them?

Mail clients can support DSNs in several ways. I list them
below in my suggested priority order:

(1) Display standardised DSNs in a standard format, which
    contains the information the user needs in easy to read
    format.

(2) Allow filtering incoming DSNs to a special folder.

(3) A command to look at a sent message, and then get a
    list of all delivery and receipt notifications for this
    message, one line per note. Something like this:

        Received by: xxx
        Received by: (printed on paper) yyy
        Delivered to: zzz
        Could not be delivered to: qqq

    This option is of course very useful in conjunction
    with option (2).

(4) Commands to request delivery and receipt notifications
    and to request supression of them.

Mail clients cannot be expected to support this until
sendmail and other MTA software starts supporting them.

------------------------------------------------------------------------
Jacob Palme <[email-masked]> (Stockholm University and KTH)
for more info see URL: http://www.dsv.su.se/~jpalme

Comments: Authenticated sender is <[email-masked]>
From: "Rolf E. Sonneveld" <[email-masked]>
Organization: Sonnection
To: [email-masked]
Date: Wed, 13 May 1998 15:16:37 +0200
Subject: Testing SMTP/ESMTP conformance
Reply-to: [email-masked]
Sender: [email-masked]

Hi, all

For one of my customers I'm looking for information on how to do 
some interoperability tests between an SMTP server and an SMTP 
client. For example I'd like to test normal SMTP functions, 
SMTP extensions (like 8BITMIME), and also test what happens if in the 
middle of an SMTP dialogue one of the two parties quit, in 
relation to the state of the SMTP session.

Has anyone ever designed a good test setup for doing these kinds of 
tests? Any suggestiongs on what I should not forget? Is there any 
reference available to SMTP test reports?

Regards,

/rolf

--

Rolf E. Sonneveld

Sonnection
Schrijnwerkerlaan 16
3828 XC Hoogland
The Netherlands
Tel./Fax. +31 33 480 3968
Mobile:   +31 6543 70 20 5
E-mail: [email-masked]
Homepage: http://www.sonnection.nl