Re: [AVTCORE] QUIC RTP Tunnelling

Bernard Aboba <> Mon, 02 November 2020 15:54 UTC

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From: Bernard Aboba <>
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Date: Mon, 2 Nov 2020 07:29:07 -0800
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To: Samuel Hurst <>
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Subject: Re: [AVTCORE] QUIC RTP Tunnelling
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A comment on the allocation of QUIC datagram flow identifiers. In pooled transports such as HTTP/3 over QUIC, the datagram flow identifier is used to route datagrams to a particular application, and an additional identifier is provided by the application to identify a particular flow. Therefore in a pooled transport the application will not have the ability to allocate its own application flow identifiers. Section 3 says:

Even flow identifiers are client-initiated, while odd flow
   identifiers are server-initiated.  This means that an HTTP/3 client
   implementation of the flow identifier allocation service MUST only
   provide even identifiers, while a server implementation MUST only
   provide odd identifiers.  Note that, once allocated, any flow
   identifier can be used by both client and server - only allocation
   carries separate namespaces to avoid requiring synchronization.

> On Nov 2, 2020, at 07:05, Samuel Hurst <> wrote:
> ´╗┐Hello,
> Apologies if this is not the correct forum for publicising this, but I
> saw from the mailing list archive that there has been previous
> discussion about mapping RTP over QUIC on this list.
> I recently published an I-D that discusses multiplexing RTP sessions
> over a single QUIC Transport connection, a technique I'm calling QUIC
> RTP Tunnelling or "QRT". This uses QUIC DATAGRAM frames to carry RTP and
> RTCP packets, with a custom flow identifier for multiplexing.
> The primary motivation behind the draft is to support live video
> contribution for media productions, but I see that it could have much
> wider-reaching applicability than that. I invite any review comments on
> the draft.
> Best Regards,
> Sam
> -- 
> (he/him)
> Project R&D Engineer
> BCS Internet Distribution
> BBC Research and Development
> 5th Floor Dock House, MediaCityUK
> _______________________________________________
> Audio/Video Transport Core Maintenance