Mo Q Media Over QUIC

Notes: Media Over QUIC
Chair: Mike English
Scribe: Will Law

Mike: should we do it?

  • Yuriy, does not solve resource provisioning, agreement on capacity. Use CDNs? to solve today. Solved ST2? (1970s).
  • Yuriy, cannot solve contribution side, needs protocol. ABR is messy, should not exist.
  • Mike - can’t guarantee resources, that is the nature of the internet.
  • Ali - real-time rate adaptation, trade off latency and quality. MoQ? gives us more tools in toolset.
  • Mike - webrtc does not have any cachability. MoQ? is good to get to broadcast scale. MOQT is a transport protocol. Streaming formats sit on top
  • Will - one network for real-time, interactive and VOD will be more cost efficient than separate networks.
  • Elijah - we have to deal with ABR in real life.
  • JP - we have 3 protocols in our “protocol”, reliable, GOP-per-stream, and datagrams, reduces latency. If you care about fairness, need a different solution.
  • Ali - how do you decide which to use? JP - does not change during session. What level of CPU overhead? About 5%. On QUIC you can understand jitter, calc acceleration of jitter, change encode bitrate.
  • Will - datagrams only solve latency if there is congestion? JP - yes. Relay does cache datagrams.
  • Yuriy - if we enable unreliable comms (datagram), then codecs should be error concealing, modern codecs do does not do this. Will anyone vendor write error concealing decoders? Prob not.
  • Will, with HEVC, can you use tiling to compartmentalize errors? Yuriy, yes, and there is slicing too.
  • JP - for audio, is unreliable datagrams.
  • Yuiry - dynamic switching of bitrates. Switching at GOP boundaries is inefficient. Look at switching at other opportunities within the codec.

Daniel - what about SVC? Mike - with MOQ, you can set stream priorities for layers, use that for SVC.

Will - what decisions is MOQ facing?

  • Yuriy, concealment
  • Mike, see clear separation of media mapping and transport objects.
  • JP - how do you implement QUIC for CDN.? Scale will be difficult. Elijah - see big uptick in QUIC traffic. Many networks are not ready for it.
  • Will, Akamai will prefer WebTransport? as public interface.
  • What congestion controller is being used? BBRv2? seems common.

Will - How long until production usage? Still needs advertising, DRM, captions. Several years.

Call to action: more implementations.