Bandwidth cost modeling


#1

Do anyone have any Excel spreadsheet model to model bandwidth costs to run a Jitsi SFU?

For example, I’d like to understand how much it costs on bandwidth on AWS ($0.09/GB) to do a 5-person Jitsi call for 1 hour.

Any help much appreciated!


Formula X# of CPU/RAM for # of connections
Unstable video/audio, depending of the environments
#2

Hey, this really depends on a lot of factors. Here is a very rough estimate:

5 x Chrome with simulcast in 720p:
in: 5*4=20 Mbit/s
out: 5+4*0.2=5.8 Mbit/s (one person on large and 4 thumbnails)
approximately 26Mbit/s so for an hour ~12GB * 0.09 = $1

5 x Firefox (no simulcast), this changes only what goes out of the server it will be same as input so 40 Mbit/s, and for an hour ~18GB * 0.09 = $1.6

And these are very rough (if correct) and in best conditions. If you change the UI to Brady bunch everything changes when using simulcast (to lower values).
Here are the values for the bandwidth used by different layers
https://chromium.googlesource.com/external/webrtc/+/master/media/engine/simulcast.cc#61


Jitsi meet server specification
Is there anyway to reduce the internet banwidth
#3

thank you damencho
what did you mean by $?
can we know for instance if i’m having a multipart conference of 15 people? any specific CPU requirements?
take care


#4

These are US dollars, these are AWS prices.
No specific CPU requirements that I can come up, the idea here is that bandwidth is the most important part, for 15 people you will need as a max to have in of 60Mbit/s and out around 80 Mbit/s this is with simulcast, if let’s say no simulcast on all participants, then you need out of around 120 Mbit/s. These values are for optimal conditions where all participants can send 720p up to 4 Mbits.


#5

@damencho
Hi Damian, is it possible to force a particular resolution in the url as an option ?
say CIF or VGA ?
What is the AWS VP server one should go if 4-5 participants streaming at 720 ?


#6

You need to pass in URL correct params for:


and

Something with 8GB of RAM and good network.


#7

thanks for your input Damian.
vinod


#8

Hi Damian,

You had mentioned about the bandwidth needed at the server side in one of the posts. Is it with H.264 ? Does jitsi support VP9 ?

If yes, how to enable it ?

Regards

Vinod


#9

The codec does not change the bandwidth so much. It is the simulcast that makes the big difference and it is described above with an example.


#10

VP9 claims to offer 50% savings in bandwidth for the same video quality. Is it possible to to enable it in place of H.264?


#11

I cannot answer that question, look around there were some issues or threads discussing that, I’m also not sure what is the state of the codec in the browsers.


#12

Hi, I would like you to explain more this figures.
1 single user with 720 p produce 4Mb/sc
5 users connected to JVB, at a ratio of 4 Mb persecond you have 5 input strimings of video, which means 20Mb/sc. Right
In the output, I understand JVB emits one person on large and 4 thumbnails, which means,
1 Usr *4 Mb/s + (4 Usr * 4 Mb *0.2) = 7.2 Mb/s. I guess the 0.2 is because of the thumbnail size reduction.

If you could explain your formula out: 5+4*0.2=5.8 Mbit/s , I’t would be appreciated.

Thank you very much, Daniel


#13

This is the output from the bridge to one participant. Sending one HD stream (5) and four thumbnails (40.2). So If you have 10 participants it will be 10(5+4*0.2) in total output. This is output from jvb.


#14

Ok, then , that one dolar (12GB *0.09) is the cost for each user connected to the room.

approximately 26Mbit/s so for an hour ~12GB * 0.09 = $1


#15

The example is for 5 simulcast participants for one hour in and out. Yeah the estimation is not correct … it is more like 20 + 29 = 49 … or I’m wrong again…