I don't mean to open a rat hole here, but has the use of gzip as part of
the yEnc encoding been seriously considered?
I understand that a compressed CTE was considered as part of the
original MIME architecture but that nothing could be agreed on at the
time. If something non-backward compatible, specific to the NNTP
medium, requiring new code be deployed, and designed for reducing the
size of files, it seems sort of odd not to compress the binary before
CRLF stuffing and shifting the NULLs.
- dan
--
Dan Kohn <mailto:dan(_at_)dankohn(_dot_)com>
<http://www.dankohn.com/> <tel:+1-650-327-2600>
Essays announced on <mailto:dankohn-subscribe(_at_)yahoogroups(_dot_)com>
-----Original Message-----
From: Charles Lindsey
[mailto:chl(_at_)clw(_dot_)cs(_dot_)man(_dot_)ac(_dot_)uk]
Sent: Thursday, April 04, 2002 01:40
To: ietf-822(_at_)imc(_dot_)org
Subject: Re: Content-Transfer-Encoding and yEnc
In <01KG3T1CQDU400004D(_at_)mauve(_dot_)mrochek(_dot_)com>
ned+ietf-822(_at_)mrochek(_dot_)com
writes:
Well, yEnc as presently formulated has a failure mode where some
messages
will grow to 2X their original size. I also don't like the fact that
it shifts the range of almost every character. It is possible to fix
both
of these problems and have an encoding with an upper bound guarantee
that
leaves the original data mostly untouched.
Just my personal take -- neither of these are necessarily showstoppers.
I think every encoding scheme has a pathological case which produces a
"2X
their original size" situation. I think such an accurrence is wildly
improbable in the yEnc case.
AIUI, the reason for the range shifting is that the NUL character tends
to
occur with more than its random probability in typical binaries (even to
the extent of huge sequences of NUL bytes). Therefore, it is desirable
that NUL itself can be transported without stuffing (or course, some
other
random character then gets saddled with that honour).
--
Charles H. Lindsey ---------At Home, doing my own
thing------------------------
Tel: +44 161 436 6131 Fax: +44 161 436 6133 Web:
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