Re: Digest, trailers and buffering was: Re: Updating Digest header RFC3230 using "selected representation"

Rob Sayre <sayrer@gmail.com> Wed, 24 July 2019 01:12 UTC

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From: Rob Sayre <sayrer@gmail.com>
Date: Tue, 23 Jul 2019 18:08:38 -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: Digest, trailers and buffering was: Re: Updating Digest header RFC3230 using "selected representation"
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On Tue, Jul 23, 2019 at 2:41 PM Lucas Pardue <lucaspardue.24.7@gmail.com>
wrote:

>  Progressive consumption implies an ability for progressive digest
> calculation, and if that cannot happen then I don't know if sending the
> digest as trailer does address trade-offs.
>

I agree that the digest is meaningless if you're doing progressive
rendering, since you can't calculate it until you have the whole message.
But you can calculate the digest as a trailer if you're doing progressive
production.

Sending the digest as a trailer reduces costs for the sender, whether it's
an upload or download. If the message is small, it's also likely that TLS
is good enough in that case.

thanks,
Rob