Subject: RFC2822bis, Message-IDs and USEFOR

From: "Charles Lindsey" <[email-masked]>
Date: Wed, 19 Mar 2008 16:11:06 GMT

Because of some unfortunate properties of Message-IDs as defined in
RFC2822, USEFOR contains some extremely ugly syntax so as to permit the
greatest possible subset of what RFC2822 allows that will nevertheless
work in Usenet. But the fact that it succeeds in doing just that does not
make it any the less ugly :-( .

We agreed way back that, when RFC2822 came up for revision, we should
press for changes that would make it more Usenet-friendly.

That revision has now taken place, and is on the verge of Last Call
(draft-resnick-2822upd-06.txt). Frank and I have been campaigning
throughout for suitable changes to be made, with occasional but useful
assistance from Russ and Alexei, and, after much persistance, we have
gained most of what we asked for (even more than I ever expected).

So, RFC2882-bis changes the suntax of <msg-id> in three ways:
   1. left of the '@', <no-fold-quote> is completely gone (leaving just
      <dot-atom-text>)
   2. right of the '@', <quoted-pair> has disappeared from
      <no-fold-literal> (indeed, it is gone from <domain-literal> too)
   3. NO-WS-CTL has also disappeared from <quoted-pair> (and from
      <quoted-string> too)

So, starting from USEFOR <msg-id> being a subset of the RFC2822 <msg-id>,
it is now almost the other way around - we allow too much! The only
remaining differences are that we still need to forbid '>', and we impose
a 250 character limit on the overall length. And I decided not to push my
luck any further by trying to fix those. I reckon we could live with them.

So the question now arises of whether we should try to bring USEFOR into
line. Granted that USEFOR has now passed its last call (even though not
yet published as an RFC), it would be necessary for us to seek leave from
the IESG to take it back for one further Draft (there is precedent for
that, since it happened that way for the NNTP draft that is now RFC3977).
I think the changes necessary are rather more than could be done at the
final AUTH48 stage.

The change that I would propose would simply be to remove that ugly syntax
and replace it with something pretty close to what is in RFC2822-bis. The
only differences needed would be to forbid '>' in <dtext> and to impose
that 250 character limit, and to apply suitable word-smithing to bring
everything else into line.

We MIGHT go further by basing USEFOR as a whole on RFC2822-bis rather than
on RFC2822. But we should make it clear before we embark on this exercise
that NOTHING else is to be changed that does not arise directly from the
RFC2822-bis changes. We have already achieved consensus on everything else
in USEFOR, and I have no desire at all to change any of that.

{The only other major difference between USEFOR and RFC2822 is that SP
after ':' in headers. It soon became clear that they were not going to
budge on that, although there was some support for a non-normative NOTE
suggesting that such as SP was a good practice for reasons of
interoperability with Usenet (and such a NOTE might yet get in).}

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131 Fax: +44 161 436 6133   Web: http://www.cs.man.ac.uk/~chl
Email: [email-masked]      Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
PGP: 2C15F1A9      Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5

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From: Harald Tveit Alvestrand <[email-masked]>
Date: Wed, 19 Mar 2008 20:09:17 +0100

Unless somehow a horde of people with lots of energy and competence 
appears on the mailing list, I'm not going to entertain proposals for 
reopening USEFOR.

Just finding the energy to call the question on the last outstanding 
USEPRO question is proving too much for these chairs.

             Harald

---

From: "Frank Ellermann" <[email-masked]>
Date: Thu, 20 Mar 2008 10:42:25 +0100

> appears on the mailing list, I'm not going to entertain proposals for 

FWIW, here's what I wrote yesterday to Lisa about this issue:

| Meanwhile I realized that replacing the normative RFC.usefor-usefor
| reference by 2822upd cannot work without reinventing the (USEFOR)
| wheel to some degree - posted on the general list yesterday.
[*]
| For 2821bis and other drafts it is difficult to decide.  But for
| RFC.usefor-usefor and the news URIs any "last minute" attempts of
| "2822upd upgrades" should be under your control.
|
| A simple recipe could be "WONTDO", 2822upd comes too late, and it
| is too easy to get "last minute" ABNF changes wrong.

*: <http://article.gmane.org/gmane.ietf.general/29592>

> Just finding the energy to call the question on the last
> outstanding USEPRO question is proving too much for these chairs.

Some foreseeable 2822upd simplifications are IMO more relevant for
EAI and mailto-bis than for USEFOR.  Mailto-bis is in the critical
path for mailto-eai + eai-mailing-lists.

Even if hordes of folks with lots of energy show up - at some point
in time somebody needs to figure out who got <toplabel> right, 4408
or USEFOR.  If ICANN seriously wants weird one letter A-<toplabel>s 
USEFOR got this "wrong" :-(  

Neither 4408 nor USEFOR mention subtle details about "xn--"... vs. 
2ALPHA "--"... labels, let alone "0x" HEXDIG.  I'm not aware of any
RFC mentioning 0x0... up to 0xf... as "bad" labels.

If RFC.usefor-usefor goes to DS these details can be fixed, that 
obviously won't happen before ID.usefor-usepro is an RFC with two
interoperable implementations.

 Frank

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From: "Charles Lindsey" <[email-masked]>
Date: Fri, 21 Mar 2008 15:51:19 GMT

>| wheel to some degree - posted on the general list yesterday.

Yes, rebasing USEFOR ON 2822upd throughout is one possibility (which I
don't entirely rule out), but my suggestion was for something simpler,
namely to leave it based on 2822, but to quietly adopt the 2822upd (modulo
the '>' difference) as the USEFOR syntax. It would still be a subset of
2822 (as it is at the moment), but a smaller one which would also turn out
to be a subset of 2822upd.

The chief advantage would be a huge simplification of that present ugly
syntax, which is surely going to be most off-putting to most readers. No
sense in off-putting readers if it is no longer necessary to do so.

>| is too easy to get "last minute" ABNF changes wrong.

It would now be so simple that getting it wrong would be quite hard work
(and would probably imnply that 2822upd had got it wrong too :-) ).

>USEFOR got this "wrong" :-(  

I think I would strenuously resist the temptation to try to fix anything
other than arises from 2822upd. The particular issue you mention is too
esoteric to raise pracitcal problems. If ICANN has sorted out the mess by
DS time, that would be soon enough. All I want to do is to get rid of that
ugly syntax if it is no longer needed, and to ensure we nevertheless still
be consistent with 2822upd.

---

From: "Charles Lindsey" <[email-masked]>
Date: Fri, 21 Mar 2008 15:56:47 GMT

>appears on the mailing list, I'm not going to entertain proposals for 

I am happy to propose the detailed changes that would be needed, if we
decide to go that route.

>USEPRO question is proving too much for these chairs.

Which is the REAL problem facing this WG. USEPRO is stymied until that
issue is resolved. We have had the dicussion. We have an agreed summary of
the pros and cons of the two options. I have three times asked (twice on
this list and once by private email) for a head count to see whether we
can achieve a consensus on one of them.