Verizon again takes crown for top U.S. LTE network, RootMetrics says

Verizon (NYSE: VZ) continues to operate the best overall network among the U.S. carriers, according to the latest study from RootMetrics, and T-Mobile (NYSE:TMUS) continues to operate the worst. But once again T-Mobile has some reason to question the results.

The network performance research firm drove more than 231,000 miles across the U.S. in the second half of 2015 to collect roughly 3.8 million test samples while driving, at stationary outdoor locations, and at more than 6,600 indoor locations. The company said it uses a variety of tools to deliver accurate results, and uses "randomized spatial sampling techniques to collect data in an unbiased manner."

Verizon operated the top network among the major carriers in RootMetrics' test with an overall performance score of 94.5; AT&T (NYSE: T) finished second at 91.3; and Sprint's (NYSE: S) 86 was good for third. T-Mobile once again finished fourth, with a score of 80.9.

Verizon also claimed the top spot in network reliability, network speed, data performance, call performance and text performance, although AT&T essentially tied at No. 1 in the latter category. T-Mobile finished last in most categories but placed third in network speed and data performance, outpacing Sprint in both tests.

Verizon hastily touted RootMetrics claim, noting in a statement sent even before the study results were released that the report marks the fifth consecutive time it has taken the crown with top overall network performance. Sprint also called attention to the study in a blog post from CTO John Saw. "We made good progress in 2015," Saw wrote in a tacit admission of the carrier's network shortcomings in the last several years, "but you haven't seen anything yet."

Wells Fargo analyst Jennifer Fritzsche said RootMetrics' results indicate Sprint's progress. "The proof of S's improving network was evident in both median download speeds, coupled with the number of markets receiving those download speeds," she said. "Importantly, RootMetrics had not recorded a median download speed on S's network of +20Mbps prior to 2H 2015, but in this report, it recorded median download speeds of +20Mbps in 14 markets."

T-Mobile CEO John Legere also blasted RootMetrics' results in a statement emailed to media prior to the official release of RootMetrics' results. "RootMetrics should be banned as an independent source for network benchmarking, period!" Legere said. "Why? Here's one example....they manipulated their testing of the T-Mobile network, choosing to turn OFF Voice over LTE, our network technology that is on every single phone we sell. VoLTE handles roughly 50% of calls made on the T-Mobile network. That is 250 million calls per day, or over 40 BILLION T-Mobile calls that RootMetrics just CHOSE to exclude in their latest tests. So the latest (and by latest, I mean up to 7 months old) RootMetrics results are worthless, and raise just one real question for T-Mobile… do we have to pay RootMetrics millions like the other carriers do to get them to stop deliberately turning off significant portions of our network and skewing results during their drive tests? Coincidence? Doubt it."

RootMetrics' study contrasts, however, with another respected study that was released a few weeks ago. The study from OpenSignal found that while Verizon's LTE network was tops in the U.S. in both coverage and speed, T-Mobile finished a very close second in both categories. And that study indicated the network gaps between all four major players have closed significantly over the last two years.

RootMetrics took flak last year when its study of mobile networks during the first half of 2015 apparently didn't measure network performance the 700 MHz band of spectrum that T-Mobile has been actively rolling out for months. Subsequently, those test results may not have captured the coverage gains the carrier may have made using those airwaves.

The company expanded its latest study to test performance in that spectrum in its latest test, but it doesn't yet test the VoLTE service that T-Mobile claims supports roughly half the voice calls on its network. RootMetrics said it will begin to test VoLTE in tests for the first half of 2016, but that lack of data may once again be penalizing T-Mobile's network performance.

For more:
- see this RootMetrics press release

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