[public-webrtc] <none>

Dom -

Your proposed message to ETSI is a good start. Unfortunately, the problems with RFC 8865 go farther than this - the specification is fundamentally incompatible with the operation of the WebRTC data channel, as noted by Harald Alvestrand [1][2].

[1]  https://github.com/w3c/webrtc-pc/issues/2931#issuecomment-1935487017

[2] https://www.rfc-editor.org/errata/eid7805




===============

  *   From: Dominique Hazael-Massieux <dom@w3.org<mailto:dom@w3.org?Subject=Re%3A%20W3C%27s%20feedback%20on%20RTT%20for%20WebRTC%20in%20EN%20301%20549&In-Reply-To=%3C9fb9ab3d-5b7c-4062-aad3-31e27d429434%40w3.org%3E&References=%3C9fb9ab3d-5b7c-4062-aad3-31e27d429434%40w3.org%3E>>
  *   Date: Thu, 15 Feb 2024 10:00:50 +0100
  *   To: public-webrtc@w3.org<mailto:public-webrtc@w3.org?Subject=Re%3A%20W3C%27s%20feedback%20on%20RTT%20for%20WebRTC%20in%20EN%20301%20549&In-Reply-To=%3C9fb9ab3d-5b7c-4062-aad3-31e27d429434%40w3.org%3E&References=%3C9fb9ab3d-5b7c-4062-aad3-31e27d429434%40w3.org%3E>
  *   Message-ID: <9fb9ab3d-5b7c-4062-aad3-31e27d429434@w3.org>

Dear WebRTC Working Group,

It was brought to the attention of the Working Group chairs that the
ongoing revision of EN 301 549 (a EU norm on accessibility) is looking
at integrating considerations on how to add real-time text (RTT) to
WebRTC-mediated calls. The current text there makes references to
RFC8865 "T.140 Real-Time Text Conversation over WebRTC Data Channels".
   https://datatracker.ietf.org/doc/html/rfc8865

As has emerged in recent discussions on the WebRTC repo [1], there seems
to be significant concerns in how good a fit RFC 8865 is for integration
of RTT in browser-based WebRTC sessions.

As a result, the WebRTC Chairs and Staff Contacts are proposing that W3C
should offer the following comment to the EN 301 549 draft committee
(where W3C has an observer seat):

----
RFC 8865 lacks important RTP packets fields for the synchronization of
real-time audio and video with RTT. RFC 8865 is ambiguous as to what
gateways need to do if there are holes due to losses when receiving RFC
4103 packets.To W3C´s knowledge, there is no mainstream implementation
of RTT using RFC 8865.

Until there is agreement on whether RFC 8865 is suitable and reliable
for RTT within WebRTC, W3C strongly recommends to qualify references to
RFC 8865 within EN 301 549.
---
(where qualifying references would e.g. include noting some of these
concerns)

Please let us know if you have any concerns with this, before Feb 21 EOB.

Thanks,

Dom


1. https://github.com/w3c/webrtc-pc/issues/2931