Ship-to-shore SAT link, 800 ms RTT, 2 % burst loss. We muxed 4 K pps telemetry + 1 Mbps H264 over QUIC last year. Head-of-line blocking vanished - TCP would have stalled 12 s on each 200 ms fade. FEC at the stream frame, not packet, let us ride fades with 3 % overhead. QUIC’s real win is acking individual frames; we saw 40 % better goodput vs TCP + application FEC at the same latency.
Very cool result, but I'm struggling to understand the baseline: what does "TCP + application FEC" mean? If everything is one TCP stream, and thus the kernel delivers bytes to the application strictly in order, what does application FEC accomplish? Or is it distributed across several TCP streams?
Pull-based streaming can work with webrtc. I implemented it for my custom ip camera nvr solution. I just open N streams on the client and when one is deactivated (typically by scrolling it out of the viewport), the client sends an unsubscribe message over a separate control channel and the server just stops sending video until they resubscribe.
I'm currently switching to a quic-based solution for other reasons, mainly that webrtc is a giant blackbox which provides very limited control[1], yet requires deep understanding of its implementation[2] and I'm tired[3].
I looked at moq-lite but decided against it for some reason. I think because I have <5 clients and don't need the fanout. The auth strategy is very different than what I currently use too.
[1] Why is firefox now picking that (wrong) ice candidate?
[2] rtp, ice, sdp, etc
[3] webrtc isn't bad for the video conferencing use-case but anything else is a pain
What was the WebRTC bug, would love to help! I saw at work that FireFox doesn't properly implement [0] I wanted to go fix after FFmpeg + WHEP.
If you are still struggling with WebRTC problems would love to help. Pion has a Discord and https://webrtcforthecurious.com helps a bit to understand the underlying stuff, makes it easier to debug.
You can convert any push-based protocol into a pull-based one with a custom protocol to toggle sources on/off. But it's a non-standard solution, and soon enough you have to control the entire stack.
The goal of MoQ is to split WebRTC into 3-4 standard layers for reusability. You can use QUIC for networking, moq-lite/moq-transport for pub/sub, hang/msf for media, etc. Or don't! The composability depends on your use case.
And yeah lemme know if you want some help/advice on your QUIC-based solution. Join the discord and DM @kixelated.
Probably never had to work with (live) video at all? I think using moq is the dream for anyone who does. The alternatives—DASH, HLS, MSE, WebRTC, SRT, etc.— are all ridiculously fussy and limiting in one way or another, where QUIC/WebTransport and WebCodecs just give you the primitives you want to use as you choose, and moq appears focused on using them in a reasonable, CDN-friendly way.
Presumably meaning nobody under 30 understands "I'm on a boat" as anything other than ancient history or boomer-speak (or more accurately perhaps millienal-speak?).
Very good progress, I have been keeping an eye on quic for some time, I have yet to use it in the wild. The article mentions the prioritization of the frames and keeping it in the RAM, I am a bit confused, so.. it’s sent delayed later or is it only added in non-priority stream? Also slightly far from that, how does that work with FEC? I built before a streaming platform for drones but it utilized gstreamer primarily over udp, different codecs based in the hardware, one of the issues was what you mentioned in the article of having one subscriber only at a time, so we had some duct tape solutions if we needed more but it wasn’t really great.
QUIC libraries work by looping over pending streams (in priority order) to determine which UDP packet to send next. If there's more stream data than available congestion control, the data will send there in the stream send buffer.
Either side can abort a stream if it's taking too long, clearing the send buffer and officially dropping the data. It's a lot more flexible than opaque UDP send buffers and random packet loss.
FEC would make the most sense at the QUIC level because random packet loss is primarily hop-by-hop. But I'm not aware of any serious efforts to do that. There's a lot of ideas out there, but TBH MoQ is too young to have the production usage required to evaluate a FEC scheme.
Looks like the situation is the same as in 2024: "Yes, except for Apple devices?" If I'm reading this right, it looks like Safari will support it next week though...
But a huge difference is that there's a plan for congestion. We heavily rely on QUIC to drain network queues and prioritize/queue media based on importance. It's doable with multicast+unicast, but complicated.
I like the ability to choose what you want to pull.
I’ve been thinking about an application where people consume all their media, and having the ability to pick which tracks to pull for any content you want to stream would be great.
Ship-to-shore SAT link, 800 ms RTT, 2 % burst loss. We muxed 4 K pps telemetry + 1 Mbps H264 over QUIC last year. Head-of-line blocking vanished - TCP would have stalled 12 s on each 200 ms fade. FEC at the stream frame, not packet, let us ride fades with 3 % overhead. QUIC’s real win is acking individual frames; we saw 40 % better goodput vs TCP + application FEC at the same latency.
Very cool result, but I'm struggling to understand the baseline: what does "TCP + application FEC" mean? If everything is one TCP stream, and thus the kernel delivers bytes to the application strictly in order, what does application FEC accomplish? Or is it distributed across several TCP streams?
Pull-based streaming can work with webrtc. I implemented it for my custom ip camera nvr solution. I just open N streams on the client and when one is deactivated (typically by scrolling it out of the viewport), the client sends an unsubscribe message over a separate control channel and the server just stops sending video until they resubscribe.
I'm currently switching to a quic-based solution for other reasons, mainly that webrtc is a giant blackbox which provides very limited control[1], yet requires deep understanding of its implementation[2] and I'm tired[3].
I looked at moq-lite but decided against it for some reason. I think because I have <5 clients and don't need the fanout. The auth strategy is very different than what I currently use too.
[1] Why is firefox now picking that (wrong) ice candidate?
[2] rtp, ice, sdp, etc
[3] webrtc isn't bad for the video conferencing use-case but anything else is a pain
I've also looked at switching my open source IP camera NVR to WebCodecs and WebTransport (maybe MoQ). Two things giving me pause:
* Firefox support for WebCodecs is poor—none at all on Android [1], H.265 is behind a feature flag. [2]
* Mobile Safari doesn't support WebTransport. Or didn't...I just looked it up again and see it does in 26.4 TP. Progress! [3]
[1] https://searchfox.org/firefox-main/rev/da2bfb8bf7dc476186dfe...
[2] https://searchfox.org/firefox-main/rev/da2bfb8bf7dc476186dfe...
[3] https://caniuse.com/webtransport
Yeah for Safari support I'm using polyfills; it sucks.
- libav.js for AudioEncoder/AudioDecoder. - QMux over WebSockets for WebTransport.
Both are NPM packages if you want to use them. @kixelated/libavjs-webcodecs-polyfill and @moq/qmux
26.4 removes the need for both so there's hope!
1 reply →
That's exciting! When you were evaluating it everything about the protocol/APIs fits your needs?
Just features/software need to be implemented?
1 reply →
What was the WebRTC bug, would love to help! I saw at work that FireFox doesn't properly implement [0] I wanted to go fix after FFmpeg + WHEP.
If you are still struggling with WebRTC problems would love to help. Pion has a Discord and https://webrtcforthecurious.com helps a bit to understand the underlying stuff, makes it easier to debug.
[0] https://datatracker.ietf.org/doc/html/rfc8445#section-7.2.5....
Absolutely agree.
You can convert any push-based protocol into a pull-based one with a custom protocol to toggle sources on/off. But it's a non-standard solution, and soon enough you have to control the entire stack.
The goal of MoQ is to split WebRTC into 3-4 standard layers for reusability. You can use QUIC for networking, moq-lite/moq-transport for pub/sub, hang/msf for media, etc. Or don't! The composability depends on your use case.
And yeah lemme know if you want some help/advice on your QUIC-based solution. Join the discord and DM @kixelated.
1. is? https://bugzilla.mozilla.org/show_bug.cgi?id=1659672
Never had to work with moq, got me to read the whole thing. There's still a place for good writing.
After all the LLM written or lobotomized^W"polished" writing that gets surfaced here, seeing human writing makes me want to do drugs and fall in love.
> Never had to work with moq
Probably never had to work with (live) video at all? I think using moq is the dream for anyone who does. The alternatives—DASH, HLS, MSE, WebRTC, SRT, etc.— are all ridiculously fussy and limiting in one way or another, where QUIC/WebTransport and WebCodecs just give you the primitives you want to use as you choose, and moq appears focused on using them in a reasonable, CDN-friendly way.
> Probably never had to work with (live) video at all?
streaming might seem like a world to you by it is a small niche of live video;)
unless it has p2p in browser support, it has nothing against webrtc for live video calls which doesn't need a server.
The Lonely Island - I'm On A Boat (Explicit Version) ft. T-Pain (Official Video) [0]
[0] https://www.youtube.com/watch?v=avaSdC0QOUM
Time flies, that video is 16 years old!
Presumably meaning nobody under 30 understands "I'm on a boat" as anything other than ancient history or boomer-speak (or more accurately perhaps millienal-speak?).
Quaid Army?
Very good progress, I have been keeping an eye on quic for some time, I have yet to use it in the wild. The article mentions the prioritization of the frames and keeping it in the RAM, I am a bit confused, so.. it’s sent delayed later or is it only added in non-priority stream? Also slightly far from that, how does that work with FEC? I built before a streaming platform for drones but it utilized gstreamer primarily over udp, different codecs based in the hardware, one of the issues was what you mentioned in the article of having one subscriber only at a time, so we had some duct tape solutions if we needed more but it wasn’t really great.
QUIC libraries work by looping over pending streams (in priority order) to determine which UDP packet to send next. If there's more stream data than available congestion control, the data will send there in the stream send buffer.
Either side can abort a stream if it's taking too long, clearing the send buffer and officially dropping the data. It's a lot more flexible than opaque UDP send buffers and random packet loss.
FEC would make the most sense at the QUIC level because random packet loss is primarily hop-by-hop. But I'm not aware of any serious efforts to do that. There's a lot of ideas out there, but TBH MoQ is too young to have the production usage required to evaluate a FEC scheme.
Do we have UDP in browser yet? Last I checked (mid 2024) it was soon-ish?
Edit: https://caniuse.com/?search=webtransport
Looks like the situation is the same as in 2024: "Yes, except for Apple devices?" If I'm reading this right, it looks like Safari will support it next week though...
Apart from actual support on real networks, isn't this the problem IP multicast was supposed to solve ages ago?
Yep, it's similar to multicast but L7.
But a huge difference is that there's a plan for congestion. We heavily rely on QUIC to drain network queues and prioritize/queue media based on importance. It's doable with multicast+unicast, but complicated.
I like the ability to choose what you want to pull.
I’ve been thinking about an application where people consume all their media, and having the ability to pick which tracks to pull for any content you want to stream would be great.
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