[Sean-Der]

What is `daily-core` actually doing? It is signaling code?

Have you evaluated webrtc-rs yet? I haven't keep up to date with mediasoup, but I saw they have a rust effort. Have you evaluated that yet?

Seems possible to drop lots of C++ dependencies :)

[jpgneves]

Hi, I'm João, one of the co-authors of this post!

Regarding mediasoup, their Rust effort so far has focused mostly on the server side of things, whereas for this particular project we would be looking more towards the client side.

That would definitely be something we are considering contributing to, as it would, as you say, drop quite a significant amount of C++ (with additional benefits on the web side, too).

[7sidedmarble]

I'm curious about the approach you guys are taking here. The client side of doing WebRTC is by far the easiest part. Maintaining separate client side implementations for mobile and web is... no harder then maintaining a web and mobile app separately anyways.

The server side is the hard part to work on. Also, one of the downsides of wasm is that it can be a pain to communicate out to the JS APIs, especially for doing lots of DOM manipulation. I'm not sure how sound this approach is really. It seems like you're going to do a lot of extra work in order to solve a problem that isn't much of a problem in the first place.

[kwindla]

I would say that both the client and the media server (SFU) side of the work are challenging in their own ways, if you are trying to support a large variety of use cases, features, and sessions with large numbers of participants.

The client-side and server-side code end up being tightly coupled and you end up having a lot more client-side code than maybe is obvious if you're building an application that uses WebRTC in one specific way. For example, handling fast subscription to and un-subscription from batches of tracks is non-trivial, but important if you're implementing "grid mode" client views.

The goal of the approach we're taking here is to be able to support a bunch of different platforms at the same level of performance, stability, and feature parity. Web, iOS, and Android are the three most important platforms. But people are also using WebRTC on Flutter, native Linux, macOS, Windows, Unreal, Unity, and various embedded platforms.

[kwindla]

We're fans of webrtc-rs, but interop considerations pretty much mean that building on top of libwebrtc is necessary for our client libraries for now.

`daily-core` is signaling, the (always evolving) low-level trickery needed to scale calls to 10,000+ participants, state management, and an opinionated internal API that lets us efficiently maintain public-facing API features like track management, and device selection.

[mwcampbell]

Have you considered releasing your Rust bindings for libwebrtc separately, either as open source or as another commercial product? I could have really used that for a desktop application I started developing a few months ago. In the absence of such bindings, I went with Electron instead, reluctantly. And no, I don't think your high-level API would be a good fit; what I'm doing with WebRTC is too custom.

Edit: Also, webrtc-rs doesn't work for me either; AFAIK, it doesn't yet have enough of the media stack, including hard stuff like echo cancellation.

[Sean-Der]

You should help out with the gaps in the media stack! That is the only way it will get better :) I don't believe echo cancellation is a hard problem either. I don't know the specific details, but I have heard this argument so many times.

People told me that unless you were a developer at a big company you can't build DTLS, SCTP and RTP Congestion Control either. Maybe the community implementations aren't as good yet, but I think it is a tortoise vs hare.

[regexident]

> You should help out with the gaps in the media stack! That is the only way

As it happens I am the author of the audio-buffer and constraint-algorithm implementations in webrtc-rs/media: https://github.com/webrtc-rs/media/commits?author=regexident

So even though we are not using webrtc-rs in Daily today, we are (or at least I am) contributing to it, in hopes of it becoming a feasible option at some point.

[yolo3000]

Are there use cases for calls with so many participants?

[vr000m]

One thing to consider is if you would have One API and a few knobs to control the experience and not have to worry about the underlying protocol-, reliability-, latency- aspects to build that experience. (particularly not worry about the shenanigans around tuning RTMP, RTP, HLS, or webrtc)

There are some use-cases in every industry. * Finance/Company: earnings calls as mentioned before, all-hands meetings at companies (with several people queuing for questions and answers) * Live Events (music or talkshows) * Tutoring or education in general. * Healthcare and education -- Surgeries which are broadcast to several schools and have active collaboration from some doctors. The large-scale interaction can begin much earlier before the surgery.

[VWWHFSfQ]

People have started turning to webrtc for broadcast streaming (1->many) instead of hls/dash because of the lower glass-to-glass latency. But it has scalability problems which makes it enormously expensive comparatively. There are low-latency variants of HLS and DASH emerging now though

[dgunay]

WebRTC is some of the lowest latency streaming you can get, so I would imagine any realtime event with a large broadcasting audience would benefit. Interactive/2-way though, that's another story.

[tebbers]

Company earnings calls with analysts? Livestreams?

[regexident]

> Have you evaluated webrtc-rs yet?

Vincent here, fellow dev at Daily, working on daily-core and Daily for iOS. :)

We did evaluate webrtc-rs, but we found that it simply isn't yet were it would need to be in order to be a realistic replacement for libwebrtc.a today. As a matter of fact I am a member of the webrtc-rs org (https://github.com/orgs/webrtc-rs/people), having contributed the audio-buffer and constraint-algorithm implementations so far (https://news.ycombinator.com/item?id=31000261).

I personally have high hopes for being able to make the jump at some point. Just alone being able to toss the monstrous `build.rs` that currently ties ninja/gn (libwebrtc), cmake (libmediasoupclient), clang (our own bridging code) and bindgen (for header imports) together and makes things work across multiple platforms would almost be worth it for me. With Rust implementations of mediasoupclient and webrtc none of this hassle would be necessary. In pure Rust stuff just works.