Subject: Removing HTTP/2 upgrade

From: Cory Benfield <[email-masked]>
Date: Wed, 17 Feb 2021 18:23:52 +0000

In the most recent interim we discussed removing the HTTP/2 plaintext
upgrade mechanism as part of h2bis. This would be a divergence from
the original specification, but HTTP/2 plaintext upgrade was never
deployed by a meaningful number of client implementations.
Prior-knowledge is substantially more common, and server implementers
have noted that they can just as easily detect the prior-knowledge
upgrade path as they can perform the HTTP/2 plaintext upgrade.

To that end I've proposed draft text that would remove the mechanism
at https://github.com/httpwg/http2-spec/pull/820. I'd like to confirm
that the working group has come to consensus on this issue, and to get
any feedback on the specific change.

Thanks,

Cory

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From: Willy Tarreau <[email-masked]>
Date: Wed, 17 Feb 2021 19:36:44 +0100

> any feedback on the specific change.

Looks good to me. Thanks for taking care of this, Cory!

Willy

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From: Alexey Melnikov <[email-masked]>
Date: Wed, 17 Feb 2021 18:49:02 +0000

Hi Cory,

> any feedback on the specific change.

Just a small question about removing registration of the HTTP2-Settings 
header field: would it be better to mark it obsolete in the IANA 
registry instead?

Best Regards,

Alexey

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From: Cory Benfield <[email-masked]>
Date: Thu, 18 Feb 2021 08:59:15 +0000

On Wed, 17 Feb 2021 at 18:49, Alexey Melnikov <[email-masked]> wrote:
> Just a small question about removing registration of the HTTP2-Settings header field: would it be better to mark it obsolete in the IANA registry instead?

Sure would, I've updated the patch to do just that.