Host (teacher) bandwidth setting adjustments

For group meetings, it is best to set your desktop Zoom app so that Enable HD in the Video tab is unchecked (see Video tab screenshot below). Also, on your account settings at https://stanford.zoom.us/profile/setting, you should set Group HD video to the lowest possible setting, which is 720p.

In general, with HD video off, everyone is set at a lower rate, so regardless of who is talking, the video stream will be at a lower quality, resulting in less bandwidth and fewer problems connecting. With HD video enabled, the active talking participant’s video would be sent at 1080p which will result in a clearer video for people who are watching, but this requires more bandwidth. If the Host allows HD video in the settings, then when students turn this on, their video stream can be sent in HD. If this is turned off from the students end, then a lower quality will be sent.

Zoom automatically adjusts the streaming resolution to match what each participant’s internet can handle. Below 720p, it may shift to 640 or 360. Also, the way Zoom works is that bandwidth requirements do not increase as more people join. Each individual user sends in their video feed, Zoom then takes all the feeds essentially merges all the feeds into a 720 video that is sent to all the participants.

If the Host is planning to Share Screen, s/he should limit their Screen Share Frames Per Seconds to 15 Seconds. This is done in the Zoom app’s Share Screen tab >> Advanced settings (See the Share Screen / Advanced tab screenshots below).

Participant (student) setting adjustments

If the Host has made the settings listed above (uncheck Enable HD in the app, set 720p in Group HD video on the web settings), but someone is still having trouble, that participant can try the following quick troubleshooting measures to address individual bandwidth limitations:

Make sure to close out as many non-essential programs prior to joining the meeting. This helps with CPU resource usage.
Leave the meeting and rejoin. This sometimes results in a better connection as different network routes are taken each time you join.
Like the host, the participant can uncheck the Enable HD feature under the Video tab of the Zoom app (see Video tab screenshot below). This will ease the upload requirements for the video they are sending out so that it doesn’t try to send an HD stream.
Uncheck the Enable Stereo Sound feature in the Audio tab from their Zoom app (see Audio tab screenshot below).
Disable the camera video from Zoom. They will still be able to listen and watch anything that is going on, even participate via audio. They just won’t be seen. This will likely yield the greatest results as it eliminates the upload requirements for the entire video stream.
Participating via the desktop Zoom application is recommended over a browser (Chrome, Firefox, Safari, Edge, etc.). Browsers only have a limited set of features and the bigger issue is that it typically would take up more resources to run on a machine. The browser also makes it more difficult to troubleshoot since it’s not dedicated to Zoom and may have other things going on in the back end. Note that this is not possible if the participant is using a Chromebook.
Another option is to switch to phone audio. However, this only makes a difference if the participant is dialing in using their carrier network. This means that they will need to disconnect the phone from their WiFi, since most phones are able to call over WiFi, which will just create 2 streams under the same bandwidth limitations. This will also help if the participant’s computer are not strong enough to handle the processing needs for both video and audio.

It may be worth trying to participate on the mobile Zoom app, but it may be hard to follow any slides on a smaller device like a phone. The features are slightly different but nothing major for a participant that would result in a bad learning experience. If they have a relatively current device, the Zoom experiences on iOS and Android are about the same.

Screenshots

Video tab
No HD

Audio tab
no stereo

Share Screen tab

Share Screen Advanced

Useful links

https://support.zoom.us/hc/en-us/articles/201362623-Changing-settings-in-the-desktop-client-or-mobile-app
https://support.zoom.us/hc/en-us/articles/207347086-Group-HD
https://support.zoom.us/hc/en-us/articles/201362663-Joining-a-meeting-by-phone

This content is thanks to UIT heroes:

Robin Tran
Blake Gentner
Mellani Miller