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Compatibility wit Netnews (was I-D ACTION:draft-resnick-2822upd-01.txt)

2007-04-27 21:26:50

In <463128C8(_dot_)6B13(_at_)xyzzy(_dot_)claranet(_dot_)de> Frank Ellermann 
<nobody(_at_)xyzzy(_dot_)claranet(_dot_)de> writes:

Internet-Drafts(_at_)ietf(_dot_)org wrote:

For the <msg-id> I'd like to see a syntax also working in NetNews,
in news URIs, and in Archived-At links when they use a Message-ID.

A "canonical" version of a Message-ID is specified in

Indeed, the Message-ID is the principal feature of RFC 2822 which could
not be incorporated into Netnews as it stood. Draft-ietf-usefor-usefor-12,
which has now been approved by the IESG, but is likely to remain in the
RFC Editor's queue until other documents referenced by it are ready for
publication, made the minimum change to <msg-id> (essentially reducing it
to a canonicalized form) that would work. That is essentially what Frank
has described, but there are other alternative possibilities involving
further restrictions which might result in a cleaner syntax.

The essential feature required for Netnews was that, in order to compare
two <mesg-id>s for equality, a simple octet-by-octet comparison would
always suffice. Such comparisons are at the very heart of the Netnews
protocol, though they hardly arise at all in email except for the purpose
of threading articles in MUAs using the <msg-id>s that occur in References
header fields. Even there, I suspect, many threaders have simply
implemented an octet-by-octet comparison.

The other principle difference is that, in each header field, an SP is
obligatory after the ":". Since this is already the universal practice
within email, I would suggest that there should be no problem in REQUIRING
the same in the case of email, and to banish the possibility of omitting
that SP to the obs-syntax.

Other differences are the omission of <comment>s in a few places (notably
Message-ID), a requirement for WSP between each <msg-id> in a References
header field (too many current threaders expect to find it there), and
requiring some non-WSP in the body of the first line of a folded header
field (this is a consequence of requiring that SP after the ":").

Life would be much simpler if Email could now be brought into line with
Netnews in these regards (the present practices would just move to the
obs-syntax, of course).

As a separate issue, it might be as well to review the whole of the
contents of the obs-syntax, but that is a matter for a separate discussion.

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