Firm's data helps you decide on a wireless network

This article was originally published March 3, 2011.

How good are the major wireless networks where you live or travel?

That's a tough question for many of us as we weigh the alternatives. Like it or not, we swim in a soup of information that mixes marketing claims, survey results, and maybe even our own bad memories from years when "dead spots" were a more common part of wireless users' lexicons.

The carriers and outside companies do "drive tests" along the nation's highways and byways. But consumers have always had limited access to the results, which the carriers do their best to spin.

RootMetrics, a young company in Bellevue, Wash., is trying to change that by making comparative data openly available at its website, www.rootmetrics.com - and by using free smartphone apps and "crowdsourcing" to expand its reach.

Some of its findings may surprise you, such as the maps of central Philadelphia displayed here that show AT&T with an edge over Verizon Wireless. I'll explain more about that showing - it largely reflects AT&T's faster data speeds - in a moment.

RootMetrics says its goal is to build a more open and transparent marketplace for data about mobile networks - "a market that democratizes mobile data." To that end, I asked RootMetrics CEO and cofounder Paul Griff to explain the company's methods as well as their limitations.

RootMetrics has used two approaches to collect real-world data on wireless networks' performance. Both center on an application for off-the-shelf smartphones.

The company started with technophiles who used BlackBerries and Androids who agreed to install beta versions of the app. It also hired its own version of "drive testers": contract workers who drive a designated route, per a navigation system's instructions, and carry four smartphones that essentially operate on autopilot.

Griff says the phones "run test scripts in a constant loop," placing calls, sending texts, uploading and downloading data, and reporting back to RootMetrics. So far, the company has enough data to offer a reliable picture of the nation's largest markets - "basically the NFL plus Los Angeles," Griff says.

That's where crowdsourcing comes in. With its iPhone app, plus a new version coming this month for the Android, RootMetrics ultimately aims to present a national picture.

"Our objective is to shine a bright light on true performance, and to recruit consumers to help populate the maps and keep them current," Griff says.

At my request, Griff aimed some of that spotlight on how RootMetrics' methods evaluate Verizon - an evaluation that Verizon and its enthusiastic customers may question.

A Verizon spokesman said via e-mail: "Verizon Wireless is the acknowledged network performance leader and that has been validated numerous times by well-respected third-party performance surveys like J.D. Power and our own rigorous internal testing, as well as independent third-party drive tests."

Is there a flaw in RootMetrics' methods? Griff resists that characterization, but says the company knows that variations in network design may affect its results and is always working to improve its model.

The company's overall "RootScore" rates carriers on a combination of two broad measures: signal strength and data transmission.

Griff says Verizon suffers for two reasons, including one that is widely recognized: its CDMA network moves data more slowly than AT&T's current version of GSM technology. That may change if Verizon stays ahead of AT&T in introducing the 4G data platform known as LTE, for "Long Term Evolution," that both companies are adopting, Griff says.

But the other reason Verizon suffers in RootMetrics' measure is less well known - and, ironically, is a network characteristic for which Griff praises Verizon.

"Verizon has built an incredibly robust network, and one of the ways they've done that is to run it at as low a power as possible," Griff says. The low power reduces "noise," he says, but also cuts its score for signal strength.

If you drill down into RootMetrics' Philadelphia maps online, you'll see that Verizon's signal strength gets tops scores in most places - data speeds are the main reason it suffers in comparison with AT&T. But Griff says RootMetrics may start factoring blocked and dropped calls into its algorithms.

"Without a signal, you can't hold a call. But on Verizon's network, the way they've engineered it, you can make and hold a call with a lower signal strength," he says.

Griff says that as its methodologies improve and as the carriers upgrade their networks, RootMetrics will offer consumers a real-time look at how their performances compare - a valuable tool if you're choosing among them.

"The real message is that there really isn't a 'best carrier,' " Griff says. "There's a best carrier for you - for where you live and work, and for how you use your phone."