Subject: #1083: USEPRO 5.3: Rules for generating message-ID

From: Russ Allbery <[email-masked]>
Date: Thu, 18 Jan 2007 20:17:22 -0800

I propose closing this ticket with no further changes.

There seems to be a rough consensus in the working group that the $alz
convention of issuing spam cancels with message IDs formed by adding
"cancel." to the beginning of the LHS of the original message ID to allow
for intentional collisions between multiple cancels for the same message
is the sort of weird stunt that can be left as an intentional protocol
violation.

The rest of the ticket is talking about namespace issues in deciding what
message IDs to use for messages.  USEFOR now defers to RFC 2822 for this,
and I think the treatment in RFC 2822 is sufficient.  This is a tricky
area, so if we can avoid having to say more about it and use the consensus
of the RFC 2822 working group, that saves us a lot of work and tricky
wording discussion.

-- 
Russ Allbery ([email-masked])             <http://www.eyrie.org/~eagle/>

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From: Frank Ellermann <[email-masked]>
Date: Mon, 29 Jan 2007 03:47:40 +0100

> I propose closing this ticket with no further changes.

I disagree.  Not talking about spam cancel conventions is okay.
Not talking about Message-IDs is not.  For UAs it can be okay
if they only try to get it right based on the text in RFC 2822.

But if an injecting agent creates Message-IDs it can't afford
to create collisions.  It has to work if it generates more than
one Message-ID per second, and it has to work if its local time
sometimes jumps backwards into the "past".  It has to work at
the end of daylight savings time, and after a reboot.

Your concept "Message-ID + Injection-Date = id" is IMO wrong. 
The id of an article is the Message-ID, as the name suggests.

The Injection-Date is a kludge dealing with incomplete history
files.  It's impossible and/or undesirable to keep a complete
list of all seen Message-IDs in practice, but it's the ideal
for worldwide unique Message-IDs forever.  

This is a core feature of s-o-1036, worldwide unique forever.

It took me very long to get this, from my Fidonet POV, where
the path is everything, and the Message-ID only optional.  I
tried weird compromises like "if two years isn't enough, then
maybe five years, or ten years".  But of course the s-o-1036
evangelists finally convinced me that "unique forever" is not
two, five, or ten years, but much longer.  And that this idea
of the Message-ID is the essence of NetNews (taking groups as
given, that was similar in FTN echomail).

Any text intending to obsolete s-o-1036 has to get this idea
to all readers (or at least to the implementors reading it).
For outsiders with a 2822-POV (Message-ID not mandatory) or
my former FTN POV it's not obvious.  It's also not obvious
why there is a history in addition to the path.  

Not talking about it (as a trick to avoid the question of a 
reasonable minimum) is no option.  S-o-1036 has this right,
and if USEPRO refuses to outline the principles of operation
it is pointless to continue with it.  Readers need to know
*_why_* something is a MUST NOT or SHOULD or MAY.  For that
they need to know how stuff works beyond their own server or
implementation.

Frank

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From: Russ Allbery <[email-masked]>
Date: Sun, 28 Jan 2007 19:10:12 -0800

> the end of daylight savings time, and after a reboot.

I think that RFC 2822 and USEFOR already adequately address this.

I certainly don't object to someone resurrecting the message ID generation
draft that was previously discussed in this working group as an
information RFC on how one can go about generating message IDs with the
desired properties, but RFC 2822 is reasonably clear about the required
properties and USEFOR already reiterates that a message identifier must be
unique forever.

> The id of an article is the Message-ID, as the name suggests.

You apparently completely misunderstood my message if that's what you got
out of it.

---

From: "Charles Lindsey" <[email-masked]>
Date: Mon, 29 Jan 2007 12:41:02 GMT

>I think that RFC 2822 and USEFOR already adequately address this.

Yes, RFC 2822 covers it, but not with the emphasis that perhaps it
dererves (no use of the phrase "for all time", for example). And all
USEFOR does is to add that the uniqueness applies across the whole of
Email, Netnews and any other protocols which might be involved, rather
than just across Emails as RFC 2822 implied.

So yes, maybe S-o-1036 expressed it better, and I would have no problem
with language in USEPRO which re-emphasised this point once again, for the
benefit of casual readers. But such language would not be normative. A
NOTE in the duties of Injecting Agents would suffice. I tend to agree that
giving reasons for why things are as they are is always a Good Thing.

>> The id of an article is the Message-ID, as the name suggests.

It is an approximation which was adequate for explaining the points that
Russ was making, but I do not think that terminology should appear in
USEPRO.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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