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T-Mobile sidesteps Wi-Fi interference

The wireless carrier tweaks its new Wi-Fi networks in Starbucks to avoid interfering with other wireless networks that are already operating in the same area.

Faster than you can say "low-fat grande cappuccino with half-decaf," wireless carrier T-Mobile beefed up its new Wi-Fi networks in Starbucks to avoid interfering with other wireless networks that are already operating in the same area.

Just before T-Mobile announced the nationwide implementation with Starbucks on Wednesday, the carrier was tipped off by a Portland, Ore., network operator that the signals from the new T-Mobile service were interfering with his Wi-Fi network.

Realizing the same interference issues potentially existed at all the Starbucks locations--already popular places to install the wireless networks--T-Mobile engineers were forced on the eve of the announcement to quickly add Cisco software to all the Wi-Fi access points so they would search for clear patches of airspace and not interfere with other networks.

The interference issues come up when two or more Wi-Fi networks bump into each other or overlap, since they share unregulated airspace. The closer a customer is to a Wi-Fi access point, the stronger the signal. But the signal decays as it reaches the edges of a roughly 300-foot radius, and interference issues arise frequently on those edges.

Two problems quickly emerge with competing networks--they "step" on each others? radius, diminishing the range of all the networks to 100 or 150 feet. Second, computers searching for a Wi-Fi network could wind up "seeing" several, toggling so quickly among them that the computer owner literally isn't given a chance to direct the computer to select one network.

It was a significant lesson in neighborliness for T-Mobile, which plans to install Wi-Fi networks in 2,000 Starbucks by year's end, making it the largest Wi-Fi network in the United States. T-Mobile is charging $30 a month for unlimited access, with walk-in Starbucks customers paying $2.99 for the first 15 minutes and 25 cents a minute thereafter.

Starbucks plans to add Wi-Fi to 70 percent of its 6,000 locations worldwide in the next few years.

Although T-Mobile is the first U.S. carrier to add Wi-Fi service to its offerings, most carriers are expected to follow with Wi-Fi services of their own. Sprint PCS has already invested in a Wi-Fi network called Boingo Wireless.

Other Wi-Fi network operators say that while they welcome T-Mobile's entry into the market, there are some competitive concerns.

"There hasn't been a lot of corporate interest in Wi-Fi up until just recently," said Adam Shand, architect of a free Wi-Fi network in Portland. "They want the same things we want for our users--good clear service. But their success doesn't always factor well with other's people's success."

Although competing paid networks haven't struck agreements with Starbucks, they are reaching deals with rival coffee bars and other gathering places. In some cases, they are working with Starbucks' neighbors, a move that allows them to compete with T-mobile even inside Starbucks.

Rick Ehrlinspiel, chief executive of rival network Surf And Sip, set up a wireless network next door to the San Francisco Starbucks where T-Mobile unveiled its service Wednesday. And Ehrlinspiel was at the press event there, distributing information about his 150-spot network and getting a peek at the competition.

His Surf And Sip's wireless network was accessible from within Starbucks during the event, albeit with a weaker signal than from Starbucks' closer and more powerful network.

His network is also a bit slower, since Starbucks is offering zippy T-1 connections. Surf And Sip typically uses more affordable connections such as cable or DSL, and has both monthly and pay-as-you-go memberships available.

T-Mobile is also butting heads with some of the earliest users of Wi-Fi, who got used to free access with what are called "public hot spots" or "community wireless." These are free wireless networks, mostly in urban areas, such as NYCWireless, which showers two major New York City parks with free wireless access.

But John Stanton, chairman of T-Mobile's North American operations, said their network is better than the free hot spots because it offers better network security and customer service.

"They (are) providing ubiquity, but threatening to be underutilized by doing things on the cheap," he said.

When Starbucks offered free wireless Internet access at the store located at Mariposa and Bryant streets' intersection in San Francisco, people used to park in front of the store at night to get free access, said Kyle Emerick, chief financial officer of Rosai Group, the Macintosh dealer next door to the Starbucks. It was enough people to prompt Rosai to start a retail business to compliment their main business, which was selling to corporate customers.

Now all the dot-coms have left the area, and while Rosai still has a storefront, Emerick points to the bars to the windows as a sign of the changing times.