Tuesday, April 6, 2021

Maximizing Zoom Performance from Home / when Bandwidth is Constrained


Maximizing Zoom Performance from Home / when Bandwidth is Constrained

Mark Katsouros

April 2021


This piece was written specifically for Zoom users at Duquesne University, but most of the tips and best practices identified here are applicable to most any cloud video collaboration platform—BlueJeans, Cisco Webex, Microsoft Teams, etc.—and to most every enterprise leveraging a work-from-home paradigm.

If you’re joining/leading Zoom sessions from home, and/or have constrained broadband connectivity (particularly in terms of upstream bandwidth, which is quite common), here are some things you can do to mitigate performance issues:

  • Turn off the competition:

o   Close other applications on your device that may be utilizing precious bandwidth (not to mention CPU cycles) during your Zoom session, particularly upstream bandwidth.

o   Same goes for other equipment in your home.  You may have to ask your son to do his gaming, or watch Netflix, at another time!

  • Within Zoom:

1.      Turn off HD video – Providing video in HD resolution requires significantly more bandwidth, so consider turning it off when the quality of the image you're sending isn't critical.  To turn off HD in your Zoom client:

a.      In your desktop Zoom client, click Settings (the gear icon).

b.      Click Video in the left-hand menu.

c.      In the My Video section, uncheck the box beside Enable HD if it is checked.

2.      Turn off your video entirely – Virtual background or otherwise, video consumes a lot of bandwidth, and typically isn’t as critical as audio.

3.      Consider using a phone (landline or cellular) for audio.  You can still join the meeting visually by computer (at least as a receiver, per bullet immediately above), but don’t join with audio from that device.  (Just close the “audio conferencing” options window when it appears, or you risk feedback and disrupting your class/meeting.)

4.      Co-host/Helper – If you have content to share, consider asking a better-connected, or on-campus, helper (co-host) to do that sharing, or consider using online collaborative documents rather than screen sharing.  Certain services, like Microsoft Office Online Documents and Teams, Box Notes, and Google Apps, let multiple people open and edit files in a shared paradigm.  These services can use less data than streaming video, while still allowing everyone to see changes in real time, or close to it.

5.      Don’t use a VPN during your Zoom session, unless you absolutely need it (for instance, if you’re trying to share content from an asset only accessible from within the University’s enterprise network).  The Duquesne GlobalProtect VPN routes all traffic, including Zoom (and Teams) traffic, through the enterprise network and border vs. directly to Zoom (and Microsoft).  (Consider #3 above.)

6.      Test your bandwidth via “http://speedtest.net”, including if you are using a VPN.  You should have at least between 1 and 3 Mbps of upload speed (depending on video format) for a reliable Zoom videoconferencing experience.  See Zoom’s bandwidth requirements for details.

7.      Cellular vs. Internet – If your available cellular bandwidth is better than your Internet/Wi-Fi bandwidth (sometimes the case, especially with today’s 4G and 5G cellular networks), consider joining your Zoom session from your cellular device’s Zoom client.  (You may need to turn Wi-Fi off.)  While this is not optimal for content sharing, it may provide an overall better video experience.  (Cellular data rates may apply.)

8.      Go into the office – If all else fails, if you have a need to share content from your device, and/or if the meeting is critical, consider going into the office / on campus.  The University’s enterprise network provides robust connectivity in both directions, and being on campus obviously negates the need to use a VPN.

9.      Zoom clients – We strongly recommend running the Zoom desktop client (vs. the Zoom web client) to improve overall performance.  Additionally, because you may often be running Zoom from somewhere on campus (and the University’s enterprise network), we strongly encourage users to install the Microsoft Installer (MSI) version of the desktop client on their Microsoft Windows machines.  The MSI version of the client contains information—files, registry data, shortcuts, and so on—that may improve performance on campus machines/networks, such as traffic prioritization.


See Computing and Technology Services’ Working Remotely FAQ for additional work-from-home tips.

Mark Katsouros is the Director of IT Support Services at Duquesne University.  Mark is responsible for the directly-customer-facing/high-touch services provided by Duquesne's Computing and Technology Services (CTS):  CTS Learning Labs (digital classrooms) and Collaboration Commons, the Duquesne Computer Store, Endpoint Engineering (enterprise configuration and mobility management), Endpoint Operations (endpoint deployment and deskside support), the IT Service Desk, and CTS Communications (MarCom).