Video and audio lag on shared internet connection

Scenario:

  • 4 person connected via same 20 Mbps internet connection
  • Bandwidth usage is around 72 KB/s upload and 210 KB/s download.
  • Video encodings used are: 360/4 @ 75 K/s, 360/2 @ 150 K/s, 360/1 @ 300 K/s

What happens:

  • Both audio and video work fine with 3 people connected, but as soon as the 4th one joins video and audio start lagging.
  • Chrome webrtc-internals doesn’t show much packet loss.
  • If a person from different network connects he will receive everyone’s video and audio, but no one from the same network gets clear audio or video.

What must be causing this issue ?

At first I thought it was related to bandwidth, but it isn’t. We tried with lower resolution and higher bandwidths.

One more thing I noticed is the video is degraded a lot with on other side with simulcast, does this have anything to do with the issue, or is it just due to compression ? I am attaching screenshots for the same.

From camera

From the receiver

  • If a person from different network connects he will receive everyone’s video and audio, but no one from the same network gets clear audio or video.

Looks like your shared Internet connection download struggles at a certain point. You’ll have to measure and troubleshoot your network link.

We tested Google Meet in same conditions and it was working fine while using same amount of bandwidth.

On 180p @ 150 K/s our solution was utilising around 100 K/s download bandwidth and same was the case with Google meet.

Note that comparing to google meet is not a good way to debug it as they have their own servers, internet routing/QoS is handled differently for goggle, …

As a general rule, we tend to ignore reports or feedback based on “solution X works better in same circumstances”.

1 Like

Okay lets not compare it, but can you just list down factors other than bandwidth might be affecting the call, on the client side or server side ?

Like congestion, packet loss, etc.

So I can have more factors to change for trial and error.