Expect-CT field name deprecation

Mark Nottingham <mnot@mnot.net> Tue, 12 December 2023 20:08 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Date: Wed, 13 Dec 2023 07:08:14 +1100
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Subject: Expect-CT field name deprecation
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*with my HTTP Field Name Registry hat on*

The Expect-CT field was registered by RFC 9163, but by the time we published it, it was clear that it was a stop-gap measure; browsers were instituting a policy to always require CT.

As a result, it's been considered deprecated by implementations for a little while; e.g.:
  - https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Expect-CT
  - https://chromestatus.com/feature/6244547273687040

Based upon this, my intention as an Expert for the registry is to request that the IESG (as change controller) approve changing its status in the registry to 'deprecated'. 

Cheers,

--
Mark Nottingham   https://www.mnot.net/