Re: msg-id

["Charles Lindsey" <chl@xxxxxxxxxxxxxxxx>]

In <20041215223053.GA9250@xxxxxxxxxxxxxxxxxxx> Thorfinn <thorfinn@xxxxxxxxxxxxxx> writes:

>On Wed 15 Dec 2004 at 08:23:00AM -0500, in <200412150823.01136.blilly@xxxxxxxxx>,
>Bruce Lilly <blilly@xxxxxxxxx> wrote:

>> I haven't the time to go into detail now, but I strongly
>> suggest that reading RFC 2822 section 3.6.4, RFC 822
>> section 4.1 and section 6, and draft-crocker-email-arch-01
>> sections 3.2 and 3.3 may help to clear up some of the
>> contradictory remarks made on this topic in this WG.

>Apart from all the quoted stuff below, I note that message-id in email
>appears to be *optional*, which it certainly shouldn't be for us.

As the USEFOR draft stands, it inherits RFC section 3.6.4, except insofar
as it explicitly modifies it.

So USEFOR _does_ make that header a MUST, and it _does_ restrict the
syntax. But it is silent on the 'uniqueness' issue, and therefore the RFC
2822 wording on uniqueness is binding for us. I see no particular reason
to change that situation.

So what does "MUST be unique" actually mean, when it comes to be
interpreted in the Real World (TM)? It means that, if ever you find a
system that has generated a duplicate message-id, you have a perfect
excuse to go and beat him about the head for being in clear violation of
the standard.

Now "beating about the head" is easier said than done in cyberspace, but
that is true of all standards violations (and let no one claim that they
"never happen").

In practical terms, if a site is persistently generating bad message-ids,
then complaining to its provider/ISP/upstream is likely to be effective,
because even the more clueless providers can see that interoperability is
being affected. But if it is one of those accidental cases that only
happens once in a thousand years, and you manage to spot it, then by all
means attempt to beat the perpetrator about his virtual head, but do not
get over-excited if his real head remains intact.

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