Re: [EXTERNAL] Re: Call for Consensus (CfC): WebRTC-NV "Low Latency Streaming Use Cases (Section 3.2)

Thank you for opening Issues 85 and 86.

Below find my personal opinion, which I'll also provide in GitHub.  I'm CC'ing Tim and Harald, who submitted the use cases, and therefore might better be able to provide "answers".

On Issue 85:

"My assumption was that "node" was equivalent to "user agent" because N39 mentions "Applications" which I assumed meant JS applications running in the browser.  With respect to whether the requirements are new, N35 talks about the ability to resend encoded media to multiple parties, but doesn't talk about metadata or bandwidth estimates. So it does seem like requirements N39 and N41 include unique aspects. "

On Issue 86:

"

Existing APIs make it possible to send containerized media (with or without DRM) over the data channel, and render it with MSE or MSEv2. This has been implemented in use cases such as cloud gaming and peer-to-peer caching (e.g. Peer5). However, there are some "gotchas":


Implementations tend to depend on support for "low latency MSE" which is not uniformly implemented.

DataChannel in Workers and MSEv2 in Workers is needed to move the receive pipeline off the main thread and remove "jank".

There are open WebCodecs issues relating to non-containerized DRM support (Issue 483 and Issue 41). If these issues were to be resolved (questionable) then allowing WebCodecs to do encode/decode using WebRTC's RTP transport, as is being advocated in other recently proposed use cases, would be sufficient to enable "support".


My personal take is that support for DRM in the WebRTC A/V stack is not a requirement.

"
________________________________
From: Jan-Ivar Bruaroey <jib@mozilla.com>
Sent: Wednesday, January 11, 2023 8:55 AM
To: Bernard Aboba <Bernard.Aboba@microsoft.com>
Cc: public-webrtc@W3.org <public-webrtc@w3.org>
Subject: [EXTERNAL] Re: Call for Consensus (CfC): WebRTC-NV "Low Latency Streaming Use Cases (Section 3.2)

I have some questions regarding Section 3.2.2. I've opened them as two issues:

  *   https://github.com/w3c/webrtc-nv-use-cases/issues/85<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fw3c%2Fwebrtc-nv-use-cases%2Fissues%2F85&data=05%7C01%7CBernard.Aboba%40microsoft.com%7C6b4083ba7c5b48fc966308daf3f4c450%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C638090529855823715%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=d8GSrs6x2H3lC6b5Zotfx4ylwpFs1KTfQ3Yh4F2%2FHck%3D&reserved=0>
  *   https://github.com/w3c/webrtc-nv-use-cases/issues/86<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fw3c%2Fwebrtc-nv-use-cases%2Fissues%2F86&data=05%7C01%7CBernard.Aboba%40microsoft.com%7C6b4083ba7c5b48fc966308daf3f4c450%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C638090529855823715%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=37j1KT1Rebmox08yH20QXbHJxFnTGMVRoaKVgozv2N4%3D&reserved=0>

Hoping for answers before responding to the CfC.

On Tue, Jan 3, 2023 at 7:20 PM Bernard Aboba <Bernard.Aboba@microsoft.com<mailto:Bernard.Aboba@microsoft.com>> wrote:
This is a Call for Consensus (Cfc) relating to the "Low Latency Streaming" use cases within the WebRTC-NV Use Cases document, Section 3.2.

The "Game Streaming" use case is described in Section 3.2.1:
WebRTC Next Version Use Cases (w3c.github.io)<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fw3c.github.io%2Fwebrtc-nv-use-cases%2F%23game-streaming&data=05%7C01%7CBernard.Aboba%40microsoft.com%7C6b4083ba7c5b48fc966308daf3f4c450%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C638090529855823715%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=lQv7Fl2ml%2FJg1eKE4x%2FSASXL2eIsc8ZcKHTKUnnS5YI%3D&reserved=0>

The "Low Latency Broadcast with Fanout" use case is described in Section 3.2.2:
WebRTC Next Version Use Cases (w3c.github.io)<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fw3c.github.io%2Fwebrtc-nv-use-cases%2F%23auction&data=05%7C01%7CBernard.Aboba%40microsoft.com%7C6b4083ba7c5b48fc966308daf3f4c450%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C638090529855823715%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=nSPE%2BhIpEi1XYRlE6PpMGIjYJv%2FbBvzEu9rqQxcC6%2BM%3D&reserved=0>

The GitHub Issues list is here:
Issues · w3c/webrtc-nv-use-cases (github.com)<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fw3c%2Fwebrtc-nv-use-cases%2Fissues&data=05%7C01%7CBernard.Aboba%40microsoft.com%7C6b4083ba7c5b48fc966308daf3f4c450%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C638090529855823715%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=DsPMm0mEAZkkXYo6mk%2F1ebr3Z%2FgbIKiWh%2BWyTPmzki4%3D&reserved=0>

In response, please state one of the following:

  *   I support addition of the "Low Latency Streaming" uses cases in Section 3.2.
  *   I object to addition of the "Low Latency Streaming" use cases, due to Issues filed in open bug <# number>

The CfC will last until midnight Pacific Time on January 16, 2023.










.: Jan-Ivar :.