Re: alpn identifiers (not again!)

ALPN was invented to deal with a shortcoming of the URI scheme.
Specifically, because we needed to use either HTTP/1.1 or (originally)
SPDY to interact with https:// resources.

I see no problem with defining h2q, if that is the way we go.  And h2
isn't in the upgrade registry because we explicitly decided not to
support that option.

On 8 June 2015 at 06:01, Stefan Eissing <stefan.eissing@greenbytes.de> wrote:
> Probably everyone is tired of this already, and yes, there are tons of mails out there and several issues on github.
>
> However. HTTP/2 is young, there are several draft specs building on top of it. The Alt-Svc spec is the prominent one stumbling over ALPN identifier use. Then there is tunnel-protocol. And more will come (QUIC anyone?). So I add my €0.02 in the hope of moving the mountain…
>
>
>
> To have „h2c“ as an ALPN identifier that can never be used in ALPN and missing „h2“ in the Upgrade: header registry (why? enable http/2 on a https connection without ALPN?) shows that there are big holes here. It is unreasonable that any new transport layer protocol would need to write new alt-svc or tunnel-protocol specs or add names into the ALPN registry that will never be usable in TLS.
>
> Will we have „h2q“ as Alt-Svc name for a DTLS secured QUIC transport of HTTP/2? Does not seem attractive to me.
>
> And we *do* already have names and registry for names that define transport protocol stacks, the URL scheme. We have
> - „http:“ as cleartext TCP HTTP/1 connection, with protocol negotiation over HTTP Upgrade
> - „https:“ as TLS secured TCP HTTP/1 connection, with protocol negotiation over ALPN
>
> With this in mind, a propsoed header like:
>    Alt-Svc: h2c=":8000", h2=":443“
> could be written as:
>    Alt-Svc: h2=„http::8000", h2=„https:“
> and in the future maybe:
>    Alt-Svc: h2=„quics::1234“
> without any confusion of ALPN identifiers and protocol stacks.
>
>
> tl:dr
>
> I think the distinction between „h2c“ and „h2" is wrong, confusing and limiting future development.
>
> //Stefan
>
> <green/>bytes GmbH
> Hafenweg 16, 48155 Münster, Germany
> Phone: +49 251 2807760. Amtsgericht Münster: HRB5782
>
>
>
>

Received on Monday, 8 June 2015 17:46:30 UTC