To improve the performance of Zoom on my slow laptop, and low speed wireless broadband connection, I am trying a router with UDP shaping. That is I slow the data flow to Zoom, to make it work better.
Previously I noticed that with Zoom in full screen mode the sound would break up and image freeze. If I reduced the window size it worked better, but this was fiddly. Also when a presenter shares their screen, Zoom tends to force the display back to full screen, after which I have to shrink it again.
An approach I tried in the past was to slow my Internet connection, which Zoom responded to by using lower resolution video, making everything more stable. However, this also slowed down all my other network use. There are software utilities which will slow just one application, but I found these did not work with Zoom.
The Internet uses two sorts of data transmission: TCP for most applications including as email and web browsing, and UDP for audio, video and interactive games. The utilities I tried to slow an Internet connection only act on TCP, not UDP, so did not slow Zoom.
Not being able to find a software solution I turned to hardware. Many routers allow for slowing, or "shaping" of the speed of the connection. A few allow this to be targeted at UDP specifically. I first tried a TP-Link TL-MR3020 V3 router (around $50 AU). This worked well with Zoom, but the modem would need rebooting every few hours.
Some reports indicated that the pocket router could not provide enough power for the Huawei E8372 wireless mode, which has an unusually high power requirement. So I then tried the slightly more expensive TP-Link TL-MR3420 desktop router. This has worked fine so far. This unit is not as portable, but has the advantage of providing four Ethernet sockets for supplying data and one for a wired modem. The unit can be configured so the wireless modem provides a backup for a wired connection.
Currently I have the data rates for UDP set to: 1024 kbps transmitting and receiving.