T-Mobile confirmed to Light Reading that it adjusted its video throttling system several weeks ago after some users began to complain that the operator was slowing video streams for customers on service plans that should have exempted them from such practices.
The issue was first brought to light on Reddit, with users complaining that streaming video services like YouTube and Netflix were being limited to 480p resolution for T-Mobile customers on plans that promised HD streaming. The issue also appeared to be related to T-Mobile's 50 Gigabyte cap -- the operator reduces some customers' speeds in congested areas if they consume more than 50 GB in a billing cycle.
A T-Mobile spokesperson declined to provide any details around the situation, including how many customers might have been affected, but said the issue had been resolved.
The dustup around T-Mobile's throttling comes as such practices and policies are examined under the microscope. Bloomberg recently reported on the results of a global, year-long study of wireless network operators' throttling practices conducted by researchers from the University of Massachusetts Amherst and Northeastern University and using the Wehe network-monitoring app. The study found that operators don't appear to have a consistent approach to video throttling, noting specifically that different video services were throttled at different rates, and customers' streams were throttled at seemingly random times of the day and night.
Importantly, the study was not able to correlate throttling with users' data plans. US wireless operators apply different throttling mechanisms to different rate plans -- for example, Verizon's new unlimited plans limit video streams to 480p resolutions on cheaper options but offer 720p resolutions on more expensive options.
To be clear, this is not the first time operators' unlimited data and throttling practices have come under scrutiny. After all, AT&T was sued back in 2014 for not disclosing the terms of its unlimited data service, while T-Mobile paid a $48 million fine in 2016 over inadequate disclosures of its own unlimited restrictions.
Critics continue to tie the issue to net neutrality, warning that operators like AT&T could favor their own video streams over those from the likes of Netflix. "The corrosive effect of favoritism should not be underestimated," wrote Colin Dixon, an analyst at news and research firm nScreenMedia. "Going forward, it is doubly important that we hold wireless operators to net neutral principals. All the top operators are beginning to roll out 5G services, which promise to deliver gigabit speeds over wireless connections. The first application operators are targeting with the technology is home broadband. Moreover, if their behavior on 4G wireless networks is deemed acceptable, they are sure to behave the same way with 5G."
But others argue that throttling is one of the many techniques that wireless network operators employ to manage traffic on their networks. "We don't live in an unlimited-resource world. There are finite resources to go around, and not everyone can have everything," said Roger Entner, an analyst and founder of Recon Analytics.
Entner argued that in the wired Internet world, operators often are able to avoid such concerns because customers are stationary and therefore network traffic is far more predictable. In wireless, however, users move around and, if they collect in one location, can put a strain on finite network resources like backhaul and spectrum. "It's really difficult, and economically challenging, when you have to build [a network] towards peak usage. Because the average usage on a wireless network is less than 10% of peak usage," he said.
As a result, Entner explained, operators often turn to network-management practices like throttling.
The problem, of course, is how to apply those practices explicitly and fairly.