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From William A Rowe Jr <>
Subject Re: "Upgrade: h2" header for HTTP/1.1 via TLS (Bug 59311)
Date Wed, 15 Jun 2016 20:32:23 GMT
Rather than put statements into Roy's mouth... here are the relevant posts
were not disputed;

It seems to me that we -can- implement
Connection: Upgrade
Upgrade: h2
on a plaintext connection, which is simply shorthand for Upgrade: TLS/1.x,
where the TLS connection *must* handshake with the ALPN token 'h2' (the 102
Switching Protocols would be followed by a TLS HELO), and that restricted
of TLS protocols and ciphers acceptable to the HTTP/2 protocol.

The advantage is plainly obvious, no need to tear down and start back up
new connection to transition to h2.

On Fri, Jun 10, 2016 at 9:22 AM, William A Rowe Jr <>

> On Fri, Jun 10, 2016 at 4:03 AM, Stefan Eissing <
>> wrote:
>> Withdrawn the proposal in r1747668 after reading the comment from Roy
>> again.
> Let's look at what Roy said... that httpd's implementation of HTTP/1.1 may
> choose
> to honor a Connection-Upgrade request header of h2, or http/2, or any
> other values
> we choose, because we are bound by the HTTP/1.1 RFC, not some arbitrary
> choice
> by the HTTP/2 RFC. Wrong RFC to change HTTP/1.1 behavior, these headers are
> only to be used in conformance with
> So the http/1.1 Upgrade response header must mirror what the server will
> honor
> for the Connection: Upgrade  http/1.1 -> {something else}
> Upgrade request value.
> My initial response is still correct, *if* httpd is willing to honor
> Upgrade: h2
> or Upgrade: http/2 request header values, then it is appropriate to offer
> these
> in the response headers. And as Roy says, we *can* do so irrespective of
> any claims within because
> that
> is not the binding specification during the http/1.1 phase of the request.
> registered the h2c token for
> the
> Upgrade token, HTTP (including HTTP/2) was already registered. However,
> no token 'h2' is registered. That doesn't prevent us or others from
> sending
> and respecting other values, SSL/ was long considered valid, but I don't
> see where 'h2' should be used in the context of the 'Upgrade' header.
> For right now, 'h2' should not be presented if 'h2' will not be honored,

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