Can Drop Mobile Data Usage Significantly
Message Center notification MC244059 (March 11, roadmap item 70786) brings news of the Teams reduced data mode for mobile clients when attending video calls. To enable the feature, Teams mobile clients for iOS and Android have a new setting to Reduce data usage. The default is Never (as shown in Figure 1) but can be set to Always or Cellular.
Choosing Cellular means that when the Teams mobile client is connected to a video call over a cellular network (4G or 5G, for instance) instead of Wi-Fi, it drops into Teams reduced data mode to minimize the demand for bandwidth. Microsoft says that the client “will deliver the best quality experience for the given meeting complexity (number of video participants, variety of bandwidth conditions, multiple modalities, etc.) limited to 500 kbps on average.”
The new mode is rolling out now and should be complete by mid-March. You’ll need an updated Teams mobile client to be able to take advantage of reduced data usage mode.
Testing Teams Reduced Data Mode
To test the effectiveness of Teams reduced data mode, I created a simple test using version 1.077.20201030302 of the iOS client (from TestFlight) on an iPhone 11 using a 4G connection.
I first joined the client to a meeting playing a PowerPoint presentation where the slides advanced on a 1-minute interval. The client was muted, so no audio was transmitted from the phone. With Reduce data usage set to Never (the default), the device consumed 158 MB of network data in 10 minutes (as reported by iOS under Settings – Cellular – Cellular Data (Current period)).
I then left the meeting and set Reduce data usage to Cellular. After resetting the iOS counter for cellular data, I rejoined the meeting for a further 10 minutes and then left. The meeting conditions were the same with a slideshow playing and advancing at one-minute intervals. The data consumed in low data mode was 45.5 MB (according to this online calculator, that’s a 71.2% decrease). The only noticeable difference in this test was the notice saying that video quality might be reduced (Figure 2). Because the PowerPoint slides are simple, I did not observe any degradation in what the Teams client displayed (this could be my eyes).
In subsequent real-life meetings involving a variety of different presentations, I have not noticed any degradation either. In fact, results have been so good that I left reduced data mode enabled for my device.
Simple Test, Good Results
My test was very simple, and it does not reflect the complexities that Teams video meetings can create when multiple video feeds for attendees are available, different content is shared, and many people talk (some concurrently). However, it proves that in an apples-to-apples test, the new reduced data usage mode uses significantly less cellular data than before (45.5 MB vs. 158 MB).
Different results might be observed in more complicated meetings, but the test demonstrates that going into reduced data usage mode will help people connect to meetings when bandwidth is scarce. It will also help people whose mobile phone plans are capped with a fixed amount of cellular data per month (and maybe explain how their data allowance has disappeared due to Teams meetings).
Learn more about the intricacies of Teams (the application, its clients, and associated applications) in the Office 365 for IT Pros eBook. Over 250 pages of Teams content will help you deploy and manage Teams to your users.
Now if only Teams would comply with not using Cellular data at all when you have Cellular Data turned off. The same issue exists with Outlook. Perhaps this is an issue with Apple where they should simply enforce that turning off of cellular data means that the app is isolated from any data exchange when not on WiFi.