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Re: proposal for issue #178

From: David Morris <dwm@xpasc.com>
Date: Mon, 7 Jun 2010 08:05:12 -0700 (PDT)
To: "'HTTP Working Group'" <ietf-http-wg@w3.org>
Message-ID: <Pine.LNX.4.64.1006070801330.743@egate.xpasc.com>


On Mon, 7 Jun 2010, Daniel Stenberg wrote:

> On Tue, 8 Jun 2010, Adrien de Croy wrote:
> 
> > I don't see any point in having an integrity check for a message containing
> > only a partial range.  Surely you want to accumulate the entire entity by
> > piecing together all the parts, and then you use the MD5 to check the total.
> 
> Imagine downloading a large file in many small chunks from many different
> servers.
> 
> In the end, you might sit there with a huge file with a bad checksum without
> being able to pinpoint the single small chunk that had the error. So now you
> need to redownload the whole thing again, instead of just regetting the small
> chunk that contained the error.

Fact of the matter is that the probablitly of getting one chunk in error 
is very low in comparison with the origin servers being out of sync being 
the reason for the error. Without an MD5 for the whole entity there is no
was to check the complete entity for correctness.

It should have been clear from the beginning that the MD5 applied to the
whole entity.
Received on Monday, 7 June 2010 15:06:25 GMT

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