Re: Updating Digest header RFC3230 using "selected representation"

Rob Sayre <sayrer@gmail.com> Tue, 23 July 2019 20:27 UTC

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From: Rob Sayre <sayrer@gmail.com>
Date: Tue, 23 Jul 2019 13:25:27 -0700
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To: Lucas Pardue <lucaspardue.24.7@gmail.com>
Cc: Roberto Polli <roberto@teamdigitale.governo.it>, HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: Updating Digest header RFC3230 using "selected representation"
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On Tue, Jul 23, 2019 at 1:12 PM Rob Sayre <sayrer@gmail.com> wrote:

> This draft looks good to me.
>
> One issue that prevented the adoption of this header and related ones
> (e.g. Content-MD5) was that HTTP/1.1 trailers had a lot of interoperability
> problems. This made it expensive for large files, or impossible to use for
> message bodies that couldn't be pre-calculated.
>

That last part is slightly wrong. I should have said it was impossible to
use for message bodies that couldn't be pre-calculated that were also
streamed. Roughly, these headers required a lot of buffering, and this
trade-off doesn't seem to be present anymore.

thanks,
Rob