LWN: Comments on "Video conferencing with Jitsi"

Video conferencing with Jitsi

wookey — Sun, 19 Apr 2020 23:31:38 +0000

For anyone interested in online conferencing options (and suddenly there are way more than there used to be ;-), this document from the Association for Computing Machinery is a useful summary of nearly everything available:
https://people.clarkson.edu/~jmatthew/acm/VirtualConferen...
and the corresponding google doc:
https://docs.google.com/document/d/1LLLniPkf48CCZyG_BNy1y...

Referenced from: https://www.acm.org/virtual-conferences

I too have been a big Jitsi meet user for years. It's worked remarkably well despite much increased usage over the last month. I'm very interested in solutions for conferences where you really want a decent-quality broadcast channel as well as low-latency bidirectional channel with optional moderator control. Debian needs to pick something, and is obviously capable of hacking things to make them better :-)

Another free option is 'Jangouts' which is a web front-end for libjanus webRTC. Looks like it may be a promising tech. Anyone with experience of libjanus vs jitsi videobridge? https://github.com/jangouts/jangouts/blob/master/README.md

No-one seems to have mentioned Apache openmeetings yet either. Any good? https://openmeetings.apache.org/

Intermediate certificate fun

mathstuf — Tue, 14 Apr 2020 13:46:20 +0000

Well, Firefox now has a solution for missing intermediates: https://lwn.net/Articles/817182/ But the general case solution implemented by other browsers look like information leaks to me (if they do AIA chasing).

Intermediate certificate fun

gevaerts — Tue, 14 Apr 2020 09:34:04 +0000

Web browsers usually cache intermediate certificates, so if you've ever visited a website that uses the same one, things will Just Work. If you had tried with a clean profile, you probably would have had the same error (but maybe in a more understandable form)

Video conferencing with Jitsi

vejeta — Mon, 06 Apr 2020 13:36:00 +0000

Are there RAM recommendations per number of concurrent users?

Video conferencing with Jitsi

nbecker — Thu, 02 Apr 2020 12:13:39 +0000

google meet seems to be subscription only

big blue button?

jch — Thu, 02 Apr 2020 10:42:05 +0000

I've been doing my lectures over BigBlueButton over the last weeks, and it's a joy to use. I upload my lecture notes beforehand, which I can annotate during the lecture; the students are able to interact (with me and with each other) over textual chat.

Just in case, one of my TAs acts as moderator, but we've only had a single case of rickrolling up to now.

The only complaint I have is that the UI for disabling the receiving of video is difficult to find, which is useful for people who pay for internet by volume or who don't want to see my face.

Video conferencing with Jitsi

stevem — Wed, 01 Apr 2020 15:21:19 +0000

"Not that your editor would have ever made any such mistakes."

*grin* BTDT...

Other options to consider

sumanah — Mon, 30 Mar 2020 19:50:23 +0000

You may find this list of tools to consider useful. Did you know that Etherpad has a WebRTC-powered video feature now? I just found out last week.

Jangouts (Janus Gateway frontend)

pevik — Sat, 28 Mar 2020 20:19:10 +0000

We use Jangouts which is Janus Gateway frontend
https://github.com/jangouts

Video conferencing with Jitsi

Sesse — Fri, 27 Mar 2020 21:00:24 +0000

I can understand why meet.jit.si doesn't; it uses 40% CPU just for sending on a measly 100 Mbit/sec of TCP! That's two orders of magnitude away from what an optimized web server does these days.

Video conferencing with Jitsi

flussence — Fri, 27 Mar 2020 18:59:34 +0000

This deficiency was pointed out *years* ago when Jitsi Meet was first released to the public. The usual barrage of excuses and deflection played out until everyone gave up trying to get through and went back to using Discord/Slack electron apps.

I'm only surprised that Jitsi doesn't have a room-moderator option to kick out broken browsers. Apparently the side effect of letting Firefox into a video call is everyone else's performance tanks? That's hardly fair.

Communing with the editors

mtaht — Fri, 27 Mar 2020 17:11:13 +0000

Certainly I know that fq_codel, cake, (and pie to some extent) make quality videoconferencing wonderful under contending loads, but I only theorize that these algos will also make p2p multi-party conferences work much better also.

(e2e there's also ongoing issues like poorly implemented rtsp feedback - so far as I know freeswitch doesn't do it still)

In the long scheme of things merely removing network jitter, latency and irrelevant loss (and even adding in-band sce or l4s signaling), is hugely important, but also encoder latency and responsiveness is a huge problem also. I miss scan lines! ( https://lola.conts.it/ )

trying to find people wit the time and motivation to tackle this has long been on my mind ( https://www.internetsociety.org/events/latency2013/ ) . I really do miss the days when making a phone call across town on the switched phone network was like wispering in your lover's ear!

And first up would be getting more folk to enable quality uplink queue management. Or show how bad it can get when you don't have it.

Video conferencing with Jitsi

frispete — Fri, 27 Mar 2020 08:19:50 +0000

It is working now. The magic trick that solved the issue was commenting out JVB_STUN_SERVERS.

Video conferencing with Jitsi

hackerb9 — Fri, 27 Mar 2020 08:15:43 +0000

(For those who don't know, WebRTC is the open standard, implemented by browsers, which Jitsi uses.)

Video conferencing with Jitsi

dskoll — Thu, 26 Mar 2020 19:40:33 +0000

You can set it up so only authorized users can create meetings, and when you create a meeting, you can password-protect it so only users you want to allow in the meeting can join it.

Initially, I just put a password on the web site using .htpasswd, but that broke the Jitsi Android app.

Video conferencing with Jitsi

vegge — Thu, 26 Mar 2020 17:35:54 +0000

> In the default setup, a new user connecting to the server will see a screen inviting them
> to create a new meeting; ...

Is there a way to set up simple access control? It looks like the default server configuration is open to the world?

big blue button?

corbet — Thu, 26 Mar 2020 14:04:14 +0000

BBB is on my list of things to look at.

Communing with the editors

corbet — Thu, 26 Mar 2020 14:03:24 +0000

Bringing in your ugly mug would stress-test the software in its own way! :)

I have been pondering various schemes, but things are still at a pretty early point, stay tuned.

big blue button?

anarcat — Thu, 26 Mar 2020 02:13:12 +0000

I have tried Jitsi a few times and it generally works well. The challenge is to scale it past a dozen people or so. Things really start to break down then. We're still trying to figure out what exactly is going on (with Firefox being one of the likely candidates) but I'm wondering of people have tried other solutions, and especially:

https://bigbluebutton.org/

AKA "BBB". That tool seems to be more "featureful" (to be polite) but seems very promising. I really like the way it allows you to whiteboard stuff together and share slides. Its moderation features also seem more advanced than Jitsi. But I'm wondering how it compares in terms of performance and ease (or not) of installation (something which Jitsi doesn't exactly shine on either).

Thanks for the review!

Video conferencing with Jitsi

mtaht — Thu, 26 Mar 2020 01:51:28 +0000

Dear Jon:

It would be pretty cool if you put up your jitsi server and invited folk into a "commune with the editors" - both as a stress test and, well, It's been pretty lonely around here lately, and I kind of miss yer ugly mug. Some virtual beer all 'round might help too.

Video conferencing with Jitsi

frispete — Wed, 25 Mar 2020 17:37:21 +0000

Thanks for this nice article. Coincidentally, I'm almost there as well. Similar to your issue, but with a different reason (unsolved): https://github.com/jitsi/docker-jitsi-meet/issues/294. What a pity, since it feels to be almost operational.

Video conferencing with Jitsi

excors — Wed, 25 Mar 2020 15:41:39 +0000

From https://jitsi.org/jitsi-videobridge-performance-evaluation/ it sounds like the key for scalability is the "last N" mode. The bridge receives streams from all participants, but only broadcasts the streams from the N most recent "dominant speakers". That means the bridge's traffic scales linearly with the number of participants, and a client's traffic scales with N (which is a small constant).

If you don't use that mode then I think it's O(num_participants^2) on the bridge and O(num_participants) on the clients, though with better constant factors than peer-to-peer: each client only has to upload their stream once to the bridge (vs num_participants-1 times to every other peer), which is good since clients usually have much lower upload bandwidth than download.

Video conferencing with Jitsi

niner — Wed, 25 Mar 2020 15:23:17 +0000

It's quite possible that I misunderstood why the video bridge helps so much (which it does). It could simply be that the video bridge is a workaround for the Firefox issues mentioned in another comment. The linked hackernews discussion indicates that with peer-to-peer as soon as a Firefox user joins the meeting, performance is degraded for all participants.

It's also likely that you're right and the central server mitigates notoriously limited upload speeds of DSL and mobile (and sadly, where I live, even cable) connections.

Video conferencing with Jitsi

sorokin — Wed, 25 Mar 2020 15:10:22 +0000

> it scales O(n) and works just so much better

I don't quite understand this. Even if all video streams get aggregated into one connection from server, that single connection still transmits n times the data.

My understanding is that total required bandwidth should be the same in both cases. Perhaps central server works better when participants' upload speed is limited?

Video conferencing with Jitsi

dskoll — Wed, 25 Mar 2020 02:31:49 +0000

I experienced very good audio quality for the duration of one call. On a other call, the audio quality sometimes got worse from time to time and sounded as you described, but I prefer a tool that degrades quality if there are link problems to one that drops audio or makes it unintelligible.

Video conferencing with Jitsi

Cyberax — Tue, 24 Mar 2020 21:41:39 +0000

It's much worse for me. It feels like it's coming from 90-s cellphone - very "metallic" sounding. Video quality is OK.

Video conferencing with Jitsi

dskoll — Tue, 24 Mar 2020 20:31:01 +0000

I gave up and installed it in its own virtual Apache server meet.example.org and it works fine. I'm very impressed with the audio quality; quite a bit better than Zoom or Skype.

Video conferencing with Jitsi

dskoll — Tue, 24 Mar 2020 15:00:27 +0000

I tried installing it on a Debian 10 box, but I wanted it to run from a subdirectory (https://www.example.org/meet/) rather than take over the root of my web space, and I just could not get it to work. Lots of googling found https://github.com/jitsi/jitsi-meet/issues/223 but no luck. :(

Video conferencing with Jitsi

karim — Tue, 24 Mar 2020 14:13:33 +0000

Over at Hackernews several people report that Jitsi has serious issues with Firefox's lack of simulcast -- several good discussion points all around regarding Jitsi real-world experience:
https://news.ycombinator.com/item?id=22669968

Video conferencing with Jitsi

Sesse — Tue, 24 Mar 2020 13:05:16 +0000

Unsurprisingly, I've been trying a whole lot of videoconferencing services recently… my experience is that Jitsi, as in meet.jit.si, is surprisingly good, although higher latency (and yes, the need for an app on mobile is suboptimal). When I last looked at it a few years ago, it was pretty much for free software people only (ie., not very usable), so there have certainly been strides here.

FWIW, so far, Google Meet, Skype, Discord are working well for me in the browser. Zoom is a disaster (the audio just consistently loses 50% of samples or so, and even when using the phone-in option for audio, it sometimes breaks up), although I haven't tried the standalone client yet.

Video conferencing with Jitsi

niner — Tue, 24 Mar 2020 12:06:16 +0000

There's a huge difference between Jitsi Meet with and without active video bridge. Without video bridge, all streams are peer to peer, so the more participants you have the more each client has to work and the more streams each participant's internet connection has to handle: O(n²). The video bridge bundles these streams on the server. This costs quite a bit of CPU on the server (but not terribly so) and obviously the bandwidth there, but it scales O(n) and works just so much better. I'm also quite sure that the video bridge is not active on meet.jit.si.

Video conferencing with Jitsi

wodny — Tue, 24 Mar 2020 11:38:57 +0000

There is also an instance at https://jitsi.riot.im/ but I don't know if audio/video chat in https://riot.im/app/ is in anyway connected to that.

The Jitsi server package also has a not so pretty postrm script which fails on reloading HTTP daemons.

Jitsi Meet burns my CPU when conferencing with something under 10 people, but works with like 2-3 people. Skype seems more efficient but with many people or with video, keyboard input starts to malfunction and the system becomes sluggish and stays that way until Skype's restart. I hope for a keylogger so no chat is lost ;)

Also had to modify the Skype package before installation because it contains chrome-sandbox (installed as setuid binary of course).

Video conferencing with Jitsi

flussence — Tue, 24 Mar 2020 07:49:36 +0000

Coincidentally I had to look at what it takes to set up a Jitsi server by hand a few days ago (someone was asking for help doing that), and it seems surprisingly painless. You need an XMPP server with a HTTPS/BOSH reverse proxy — an existing IM-only setup would work — and then Jitsi plugs in as three extra daemons: two XMPP components and one HTTP API.

The official docs make it sound a bit scarier than it actually is: https://github.com/jitsi/jitsi-meet/blob/master/doc/manua...

Video conferencing with Jitsi

wojas — Tue, 24 Mar 2020 07:05:22 +0000

Thanks for this article!

I just set it up using their official Docker Compose config, which was a breeze:
https://github.com/jitsi/docker-jitsi-meet

Video conferencing with Jitsi

marcH — Tue, 24 Mar 2020 03:16:33 +0000

For communication software like this, I think open standards are even more important than open-source. I'm surprised the article didn't mention WebRTC once.

Video conferencing with Jitsi

mtaht — Tue, 24 Mar 2020 02:31:43 +0000

I too started looking at jitsi this past week - but got stuck probably on the same points you documented just now, and you fixed, hopefully. thx!

I got interested, because, well, the binary blobs in zoom trouble me. Not huge on those. Also the nature of the bridge itself: "Look! it's all encrypted until zoom hq gets it!". I figure they implement CALIA ( https://en.wikipedia.org/wiki/Communications_Assistance_f... ) fully....

I have a different usage model however than the cloud. It was my hope that tons more folk would have enough uplink bandwidth to actually run a service like this in the home or "on campus", rather than the cloud. And try to leverage ipv6.

Plug: take a look at freeswitch?

And then there's this: https://peerjs.com/index.html

Video conferencing with Jitsi

gwolf — Tue, 24 Mar 2020 02:13:28 +0000

I have long been a Jitsi user — Of the lowest kind (that is, I don't even run my own server, but am a client at the canonical implementation, https://meet.jit.si/ ). I have insisted my peers on using Jitsi as it does not require user data to be yielded; no registration is required, just connect and use.
Given COVID-19, I have moved my classroom over to Jitsi, and finally got around to configuring the Youtube recording feature. Not that I want to push my videos here (no monetization on them, promise!), but if results interest you, you can find them at https://www.youtube.com/channel/UCDqXtc9GxROhLvFQ4bX6PLg
My first Jitsi class' recording was cut short shortly after ~37 minutes (plus ~5min at the beginning where I was fiddling with stuff), but the second one was quite smooth. I had at one point 31 people connected (mostly muted both of microphone and camera), and had no quality issues. I had a guest speaker, and we interacted quite good as well.
So... I'm just sending an experience report here. I love Jitsi! :-)