Re: [AVTCORE] Response to W3C WebTransport WG Request from IETF 112

[Jonathan Lennox <[e-mail]>]

> On Apr 11, 2022, at 1:34 AM, Spencer Dawkins at IETF <[e-mail]> wrote:
> 
> But even if we don't need to choose between media-oriented congestion controllers, we would need a QUIC extension to allow us to say "we're doing media, so don't use the congestion controllers you might use for non-media traffic". 
> 
> I suspect the QUIC working group would be a fine place to work on that extension (and if we did it anywhere else, QUIC would either ask, or be asked, to review that work anyway). 

It’s not clear to me that you need a *protocol* extension to signal this?  Monolithically, a sender knows that it’s sending media, and can choose its congestion control algorithm appropriately.

You definitely would need *API* signaling to indicate from the application to the QUIC stack that media is being sent, and thus an appropriate low-latency congestion controller should be chosen.  This is absolutely relevant to the W3C API, and thus should probably be communicated in the liaison statement response.

(There may be QUIC protocol extensions needed to support these low-latency congestion controllers, probably something like draft-huitema-quic-ts, but I think work’s ongoing on that pretty well already.)