Re: 426 Upgrade: HTTP/3.0

I agree, this is strange enough to be worth correcting in some fashion.

--Ben
________________________________
From: Jan Schaumann <jschauma@netmeister.org>
Sent: Tuesday, July 1, 2025 2:14 PM
To: ietf-http-wg@w3.org <ietf-http-wg@w3.org>
Subject: 426 Upgrade: HTTP/3.0

Hi,

I just noticed that RFC9110 says in section 15.5.22
https://urldefense.com/v3/__https://httpwg.org/specs/rfc9110.html*status.426__;Iw!!Bt8RZUm9aw!_hTbaQivdJDCLhL-sh44l4WDIxbTmjS_ZpWmImxfxOeNGr-qfiHOPG8-mGyTYAdQL0bM1jfSo2UbNVGX$

"Example:

HTTP/1.1 426 Upgrade Required
Upgrade: HTTP/3.0
"

Seeking an upgrade to H3 would entail a switch in
connection protocol, but further down in section 7.8,
RFC9110 also explicitly says

"The Upgrade header field only applies to switching
protocols on top of the existing connection; it cannot
be used to switch the underlying connection
(transport) protocol, nor to switch the existing
communication to a different connection. For those
purposes, it is more appropriate to use a 3xx
(Redirection) response (Section 15.4)."


So these two parts seem to contradict each other, and
the 'Upgrade' section should use a different example?

-Jan