Study claims streaming video apps are being throttled by wireless carriers

Researchers from Northeastern University and the University of Massachusetts say online video apps like YouTube, Netflix and Amazon Prime are being throttled on wireless networks. The ongoing study, which is being conducted through the mobile app Wehe, is tracking which carriers are slowing traffic and on which mobile apps. According to a report from Bloomberg, the Wehe study is “likely is the single largest running study of its kind.”

The Wehe app has been downloaded by some 100,000 consumers. The app measures how fast a particular service, like Netflix, is delivered to end users on mobile devices across different wireless networks and compares those speeds with available network speeds. So far, the app has conducted over 500,000 tests across 2,000 ISPs in 161 countries. In these tests, YouTube was the most throttled mobile app. Netflix, Amazon Prime, and the NBC Sports app were also subject to data speed slowdowns.

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Researchers measured “differentiation”—instances in which certain traffic on a network is treated differently than other traffic—across US wireless carriers. According to Bloomberg, most of that activity was throttling. A recent test, for example, found Netflix being delivered at 1.77 Mbps on T-Mobile’s network, while other traffic on the network had speeds of 6.62 Mbps available.

The app detected differentiation 11,100 times on Verizon’s network. The app detected differentiation 8,398 times on AT&T’s network. Differentiation was detected 3,900 times on T-Mobile’s network, and 339 times on Sprint’s network. Because the app measures instances of differentiation, the numbers are partly influenced by how large the user base is. The full study will be released once researchers have collected a full year’s worth of data.

David Choffnes, developer of the Wehe app and a co-author of the study, is working with the French government to use the app to monitor net neutrality adherence in France. Bloomberg reported that Choffnes is also working with Verizon on another as-of-yet-unpublished study on speeds and throttling across wireless carriers’ networks.

Wireless carriers say they use throttling to manage network congestion. High-quality videos from the most popular online video apps like YouTube can become onerous during peak traffic times, when the multitudes of mobile users are all trying to access the network at once. But some carriers have found themselves in hot water for degraded speeds for certain types of traffic on wireless networks. Verizon, for example, recently apologized for throttling speeds for firefighters in the midst of battling a California wildfire. And AT&T recently wrapped up a lawsuit with the FTC over alleged throttling of speeds for customers on its older unlimited data plans.

RELATED: Verizon admits mistake in throttling firefighters’ LTE speeds

"We are committed to an open internet. We don't block websites. We don't censor online content. And we don't throttle, discriminate, or degrade network performance based on content," AT&T said in a Sept. 5 statement provided to FierceWireless. "We offer customers choice, including speeds and features to manage their data. This app fails to account for a user’s choice of settings or plan that may affect speeds. We’ve previously been in contact with the app developers to discuss how they can improve their app's performance."

Article updated Sept. 5 with statement from AT&T.