The largest US telecom companies are slowing Internet traffic to and from popular apps like YouTube and Netflix, according to new research from Northeastern University and the University of Massachusetts, Amherst.
The researchers used a smartphone app called Wehe, downloaded by about 100,000 consumers, to monitor which mobile services are being throttled when and by whom, in what likely is the single largest running study of its kind.
Among US wireless carriers, YouTube is the No. 1 target of throttling, where data speeds are slowed, according to the data. Netflix Inc’s video streaming service, Amazon.com Inc’s Prime Video and the NBC Sports app have been degraded in similar ways, according to David Choffnes, one of the study’s authors who developed the Wehe app.
From January through early May, the app detected “differentiation” by Verizon Communications Inc more than 11,100 times, according to the study. This is when a type of traffic on a network is treated differently than other types of traffic. Most of this activity is throttling.
AT&T Inc did this 8,398 times and it was spotted almost 3,900 times on the network of T-Mobile US Inc and 339 times on Sprint Corp’s network, the study found. The numbers are partly influenced by the size of the networks and user bases. C Spire, a smaller privately held wireless operator, had the fewest instances of differentiation among US providers, while Verizon had the most.
“If you are a video provider, you have a patchwork of different carriers doing different things to your network traffic,” Choffnes said. “And the patchwork can change any time.” Consumers often don’t know about this throttling, he added, noting that he discovered AT&T began slowing down some of his apps earlier this year.
Carriers say they’re throttling to manage Internet traffic. To deliver the videos people want to watch on their phones, sacrifices in speed are required, according to the three largest US wireless companies, Verizon, AT&T and T-Mobile. Terms-of-service agreements tell customers when speeds will be slowed, like when they exceed data allotments. And people probably don’t notice because the video still streams at DVD quality levels. If you want high-definition video, you can pay more, the carriers say.
While slowing speeds can reduce bottlenecks and congestion, it raises questions about whether all traffic is treated equally, a prime tenet of net neutrality. The principle states that carriers have to treat all data on their networks the same, and not discriminate by user, app or content. The US Federal Communications Commission under President Barack Obama enshrined net-neutrality rules in 2015. After Donald Trump won the 2016 election, a Republican-led FCC voted to scrap the regulations.
The Wehe app has so far conducted more than 500,000 tests involving more than 2,000 Internet service providers in 161 countries. It measures how fast each wireless network delivers video from services like Netflix and YouTube and compares those speeds with the network speeds available at that time. For example, in one recent test of the app, Netflix speeds were 1.77 megabits per second on T-Mobile, compared with the 6.62 megabits-per-second speed available to other traffic on the network at the same time.
In recent months, Choffnes has become a new kind of net-neutrality watchdog since the FCC vote in 2017. He’s been retained by the French government to use the Wehe app to audit for net-neutrality violations. State and local governments in the US have come calling, too. Choffnes said he also shared his findings with the US Federal Trade Commission, which took over the job of policing US Internet service providers from the FCC.
“Efforts like Wehe are an important approach to detect whether Internet service providers are engaging in traffic shaping, i.e., slowing down traffic of certain online services or apps,” said Florian Schaub, a privacy and mobile-computing expert at the University of Michigan. “Now that net neutrality has been repealed by the FCC, it is important for consumers and researchers to watch out for ISPs starting to make use of their new 'freedom’ in that way, and then call ISPs out for it.”
Throttling was happening well before the FCC stopped enforcing net neutrality. T-Mobile has been streaming video at different speeds since it started offering free streaming through Binge On in 2015. It was an agreement between customers, T-Mobile and video providers like Netflix.
“We do not automatically throttle any customers,” said Rich Young, a Verizon spokesman. “To manage traffic on our network, we implement network management, which is significantly different than blanket throttling.”
John Donovan, head of AT&T’s satellite, phone and internet operations, said “unequivocally we are not selectively throttling by what property it is. We don’t look at any traffic differently than any other traffic.”
He compared AT&T throttling to an electricity grid where some customers sign up for rolling blackouts in return for cheaper service. That’s what Choffnes’s research is detecting, the AT&T executive said. “We talked to him about some of his methodologies,” he added.
Choffnes’s work is funded by the National Science Foundation, Google parent Alphabet Inc and ARCEP, the French telecom regulator. Amazon provided some free services for the effort, too. He even has a deal with Verizon to measure throttling at all US carriers for a public report that’s yet to be published. Choffnes said Verizon can’t restrict his ability to publish research and the companies that support him don’t influence his work.
Choffnes became an Internet celebrity in December, when Apple Inc rejected his Wehe app from the App Store. He tweeted about it, and the news website Motherboard wrote about it. Following an outcry, Apple approved and published his app. Wehe had only a handful of users before the episode, but quickly gained tens of thousands new testers.
The net-neutrality debate came to the forefront again in recent days after Verizon limited the data speeds of California firefighters as they battled a blaze. The company said it made a “customer-support mistake” in limiting access to emergency responders.
“As we saw with Verizon throttling the Santa Clara County Fire Department, ISPs are happy to use words like 'unlimited’ and '€no throttling’ in their public statements, but then give themselves the right to throttle certain traffic by burying some esoteric language in the fine print,” Jeremy Gillula, tech policy director at Electronic Frontier Foundation, said.
“As a result, it’s especially important that consumers have tools like this to measure whether or not their ISP is throttling certain services. Only tools like this can really keep ISPs honest.”
With no federal net-neutrality rules in the US, legislators and regulators from state and local governments including New York City and Massachusetts have reached out to Choffnes for advice on writing their own replacement rules, he said.
“I’ve always wanted to focus on areas where not only I benefit as a user but also pretty much everyone else will benefit,” he said. “Problems where we can have a real-world impact.” His prior work includes ways to improve download speeds of BitTorrent, an online service that’s used for sharing files.
Once Wehe collects a year’s worth of data, Choffnes hopes to present the trove at a major technology research conference. His recent paper on the project was rejected by the Internet Measurement Conference partly because it didn’t have 12 months of data, he said.
With his app, Choffnes said he wants to give regulators the tools to monitor the marketplace.
“I would not contest the term watchdog – that was certainly was the goal of our project,” he said. – Bloomberg