Re: H3 ALPN?

[Dragana Damjanovic <[e-mail]>]

On Wed, Apr 28, 2021 at 4:28 PM Martin Duke <[e-mail]> wrote:

> I misremembered the previous discussion; it was on the list, not on Slack,
> so it's archived. It starts here:
>
> https://mailarchive.ietf.org/arch/msg/quic/AQM3or1TNnInYhWe8UEx5B6nrgw/
>
> I believe the conclusion was that we would use 0x00000001/h3 as soon as
> QUIC RFCs shipped, before H3 RFCs shipped.
>
>
That works for me as well.
The neqo(our quic/http3 library)  already implements this. This is
currently not exposed in Firefox.

Dragana


> On Wed, Apr 28, 2021 at 7:22 AM David Schinazi <[e-mail]>
> wrote:
>
>> Google's implementation uses a 1:1 mapping between
>> an h3 ALPN and a QUIC version. Because of this, when
>> we ship QUIC 0x00000001, it'll be with ALPN=h3.
>>
>> Our code supports v1/h3 already, but v1/h3 is disabled by default.
>> We'd like to align with everyone to pick a date when we start
>> enabling v1/h3 in production though.
>>
>> From the conversations I've had, I think everyone agrees that
>> when draft-ietf-quic-http ships as RFC, everyone will be allowed
>> to ship v1/h3. I think everyone also agrees that we shouldn't do
>> that before draft-ietf-quic-transport ships as RFC.
>>
>> The open question is: do we wait for draft-ietf-quic-http or do we
>> move forward when draft-ietf-quic-transport ships?
>>
>> David
>>
>> On Tue, Apr 27, 2021 at 4:04 PM Martin Duke <[e-mail]>
>> wrote:
>>
>>> QUIC, sorry the confusion. The original message in this thread included
>>> HTTPbis, and you should reply to that one to keep everyone in the loop.
>>>
>>> On Tue, Apr 27, 2021 at 3:59 PM Martin Duke <[e-mail]>
>>> wrote:
>>>
>>>> Damn it, wrong http
>>>>
>>>> On Tue, Apr 27, 2021 at 3:40 PM Martin Duke <[e-mail]>
>>>> wrote:
>>>>
>>>>> In the quicdev slack channel today, we realized that we had a
>>>>> disconnect on what ALPN to use in the interval between the QUIC RFCs
>>>>> publishing and the HTTP/3 RFCs being ready (due to a MISREF with
>>>>> http-semantics, etc).
>>>>>
>>>>> It's lost in the slack archives now, but I *think* we had concluded
>>>>> that once the QUIC RFCs ship the endpoints should use 0x00000001/h3, not
>>>>> h3-29 or h3-32, because the chance of something in http-semantics breaking
>>>>> interoperability was nil. I personally don't really care how we converge,
>>>>> as long as we converge.
>>>>>
>>>>> To summarize the choices, in the ~months between the RFCs, are
>>>>> endpoints doing a QUIC version + ALPN of
>>>>> 1) 0x00000001/h3 or
>>>>> 2) 0x00000001/h3-xx
>>>>>
>>>>> Can we come to an agreement on this point?
>>>>>
>>>>> Martin
>>>>>
>>>>