Re: AD Evaluation of draft-ietf-httpbis-tunnel-protocol-03

For quite some time, we've used NPN and ALPN to denote a "protocol stack" - e.g., "h2" vs. "h2c"*.

However, this confusion does still keep coming up. I think what we need here is some explanatory text that spells out how ALPN is being used — and that this text should also turn up in other places that use ALPN like this (such as Alt-Svc).

Cheers,


* See also: <https://github.com/http2/http2-spec/issues/417>


> On 3 May 2015, at 7:02 am, Adrien de Croy <adrien@qbik.com> wrote:
> 
> 
> 
> ------ Original Message ------
> From: "Martin Thomson" <martin.thomson@gmail.com>
> To: "Mike Bishop" <Michael.Bishop@microsoft.com>
> Cc: "Barry Leiba" <barryleiba@computer.org>; "draft-ietf-httpbis-tunnel-protocol@ietf.org" <draft-ietf-httpbis-tunnel-protocol@ietf.org>; "draft-ietf-httpbis-tunnel-protocol.shepherd@ietf.org" <draft-ietf-httpbis-tunnel-protocol.shepherd@ietf.org>; "HTTP Working Group" <ietf-http-wg@w3.org>
> Sent: 2/05/2015 6:26:34 a.m.
> Subject: Re: AD Evaluation of draft-ietf-httpbis-tunnel-protocol-03
> 
>> On 1 May 2015 at 11:14, Mike Bishop <Michael.Bishop@microsoft.com> wrote:
>>>>   The ALPN identifier and registry are used to identify a protocol, not
>>>>   a single protocol layer or component.
>>> 
>>> This feels like the same issue from the other thread -- this phrasing makes it sound like you mean "protocol" to imply a stack/suite, "not a single protocol layer..."  So now we're not just overloading the ALPN registry, we're overloading the word protocol!
>> 
>> On the contrary, protocol layers != protocols.
> I disagree
> 
> IP is a protocol
> TCP is a protocol
> TLS is a protocol
> HTTP is a protocol
> 
> 
> 
> 
>> 
>>> If it's TLS, this header copies the list from the ClientHello field; if it's not TLS, it contains the token that would be in ALPN if the client wanted to negotiate this protocol over TLS.
>> 
>> Except that if it was over TLS it would be a different thing entirely.
>> 
> 

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

Received on Monday, 4 May 2015 03:09:12 UTC