Sorry, I should have made these comments before, but recent threats of
Last Calls have brought it rapidly to the top of my 'todo' list :-( .
The principlal change in this latest draft is the removal of
<quoted-string> from the <id-left>. This is much to be welcomed, but it
still does not address several other Netnews incompatibility problems that
I raised in my original message entitled "Compatibility with Netnews"
which I posted on April 27th.
I also have some niggles with the latest draft not related to Netnews, but
I shall save those for a separate thread. So here are the issues that
remain vis a vis Netnews.
1. Message-ID
-------------
The latest change is a huge improvement, but some niggles still remain.
Netnews has a requirement to be able to compare two msg-ids by a simple
octer-by-octet comparison (which also implies case sensitivity). That
surely is a desirable aim for Email also, and indeed it would be useful to
mention that property in the paragraph of section 3.6.4 that starts with
"The message identifier (msg-id) MUST ...". But we are not quite there
yet, because a <quoted-pair> is still allowed within a <no-fold-literal>.
True, there is a mention that "other specifications" will limit it, but no
such specifications are mentioned. Pointers to
draft-ietf-usefor-usefor-12 and to RFC2821-bis would be in order here (cf
such a mention in 3.4.1).
However, I cannot conceive that any future IP-address format or other
domain literal would ever contain a <quoted-pair> or any whitespace (that,
together with '>', is the other thing Netnews cannot tolerate at this
point) - there are just too many existing protocols that would promptly
fall over. So why not fix the problem once and for all now? And fix it for
<domain-literal> at the same time - that and <no-fold-literal> and the
only places where <dtext> and <dcontent> are used, so it is easily done,
and the obs-syntax would remain, of course.
And finally, a couple of nits I have spotted:
In 3.2.2, in the Note:, "no-fold-quote" no longer exists, and
"no-fold-literal" need not be mentioned because the mention of "dcontent"
covers it.
In 3.6.4, near the bottom of page 27, you need to add quoted-strings to
the list of things now not allowed in msg-ids.
2. SP after the ':' in headers
------------------------------
That is REQUIRED in draft-ietf-usefor-usefor-12, and it is REQUIRED in the
new NNTP standard RFC 3977. Since every known MUA already generates
headers that way, it would cost nothing to require it here also, and of
course the obs-syntax would still allow its omission to be accepted.
There is one slight consequence that you should then forbid header lines
with only whitespace after the header-name (because trailing whitespace
has a habit of getting lost).
3. CFWS between msg-ids in References
-------------------------------------
It is currently [CFWS], but usage in Netnews has always placed whitespace
there (and References has always been more of a News featrure than an
Email feature). Would it hurt to REQUIRE it?
And also, please can we promote its use in Replies from SHOULD to MUST? It
was SHOULD in RFC2822, but many MUAs have not taken the "hint" and, as a
result, threading in mailing lists often gets broken, which is a
confounded nuisance. It is invariably done properly within News.
4. Allowed positions for <comment>s
-----------------------------------
Allowing <comment>s in Message-ID header fields will break Netnews, and
therefore the Usefor draft disallows them. Would it hurt to bring Email
into line? For sure nobody ever uses them there.
--
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: chl(_at_)clerew(_dot_)man(_dot_)ac(_dot_)uk Snail: 5 Clerewood Ave,
CHEADLE, SK8 3JU, U.K.
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