Wireless Anywhere -- Even Miles from an Access Point?

By Gerry Blackwell

April 22, 2002

Will multimode technology render access points obsolete and allow 80211 users to access a network from anywhere? That's the vision pushed by VoiceStream, which last month announced its intention to merge 80211 and 2.5G technologies into a single product offering. Cole Brodman, senior vice president of product management, discusses VoiceStream's plans to integrate Wi-Fi hotspot and mobile wireless networks.

Commercial Wi-Fi hotspots are a neat idea. The trouble is, they're not everywhere -- or even very many places yet. So what do you do when you're not at the airport or your hotel and can't find a Starbucks?

Networks of free Wi-Fi hotspots operated by community volunteers may eventually offer a solution, but the pace of build-out will be uneven -- and the networks themselves likely won't be terribly reliable.

A better bet is integrating mobile wireless and Wi-Fi hotspot networks. That's what Bellevue WA-based GSM service provider VoiceStream Wireless and sister company T-Mobile International -- which earlier acquired the assets of MobileStar Network Corp. -- are doing.

VoiceStream, which was purchased last year by Deutsche Telecom AG, has seven million customers and offers GSM service in 39 states, covering 96 percent of the U.S. population, or 270 million people. T-Mobile, also a Deutsche Telecom subsidiary, offers GSM service in four European countries.

VoiceStream CEO John Stanton unveiled the company's vision of seamless global connectivity at the CTIA Wireless 2002 conference in Orlando FL in March. We talked to senior vice president of product management Cole Brodman recently to get the details.

Integrating the two companies' Wi-Fi hotspot and mobile wireless networks will be a three-phase project over about two years, Brodman explains.

In the first phase, within the next six months, VoiceStream will offer a bundled, one-bill service. Subscribers will likely pay less if they take both than they pay now for each separately. At participating Wi-Fi hotspots, they will be able to connect at 802.11b speeds. Away from the hotspots, they'll be able to connect over VoiceStream's GSM-GPRS wide area network.

GPRS (General Packet Radio Service) is a packet data overlay for GSM mobile telephony networks -- one of the so-called 2.5G technologies on the evolutionary path to 3G. It theoretically delivers up to 115 Kbps, but the average real-world rate is about 40 Kbps.

That is still much faster than 2G mobile networks, and plenty fast enough for low bandwidth applications like e-mail and calendar synching, Brodman says.

The two networks will continue to operate separately in this first phase and maintain separate pricing plans -- by the kilobit for GPRS, by the hour, day or month for Wi-Fi.

In the second phase, within 12 months, VoiceStream and T-Mobile will integrate network systems so that subscribers will never have to re-logon or even re-authenticate as they move from GPRS WAN to Wi-Fi hotspot and back again. And the companies will by then be able to market multimode Wi-Fi/GPRS PC card modems.

VoiceStream is working with both Nokia and Cisco, both of which are close to bringing network integration technology and multimode PC modem cards to market, Brodman says. T-Mobile is already doing internal trials of some of this equipment in Europe, and VoiceStream will begin trialing in the United States soon.

The integration will probably be made possible by having one subscriber profile, which will be stored on a GSM SIM card -- the tiny smart card in GSM phones that carries subscriber information. The multimode Wi-Fi/GPRS PC card will have a SIM card slot in it, Brodman explains.

At this point pricing plans may also come together. And the good news is that it seems likely it will be Wi-Fi-style fixed-rate pricing.

"More and more customers are looking for pricing models that allow for fixed connectivity costs," Brodman says. "So it may be that we'll have to move into the all-you-can-eat world [for GPRS]. It's something we're trying to study now to understand customer demand."

This second phase of the Wi-Fi/GPRS project will also overlap the next stage in the evolution of GSM networks toward 3G. VoiceStream expects to begin deploying EDGE (Enhanced Data GSM Environment) technology late this year and begin offering commercial service in mid-2003. EDGE promises a theoretical bandwidth boost to 384 Kbps for GSM mobile networks. Practically speaking, it will be more like 100 Kbps, Brodman says.

The third phase, in which VoiceStream could offer seamless hand-off between GPRS and Wi-Fi networks, is less definite. "I wouldn't exactly say it's [a] theoretical [capability], but it's more something in development than a product that's on a firm roadmap," Brodman says of intermodal hand-offs.

Big questions about it remain, which VoiceStream doesn't believe it will be able to answer until it begins to trial the technology later this year.

For some applications, such as e-mail, which does not rely on low latency, hand-off between networks should be fairly easy to manage, Brodman says. The system would just buffer the incoming (or outgoing) data until the hand-off has been made and then continue transmission.

But how many customers really want or need to be able to walk from one coverage area to another and maintain constant downloading or uploading of e-mail?

And then there are applications that do require low latency, like audio and video, where slick, cellular-style hand-off between coverage areas would be vital to maintain quality. But again, who will want or need this capability?

"It's unclear to us which applications we'll need to be able to move seamlessly," Brodman says. "We can envision some, but will they be so prevalent that they'll be need-to-have or will they just be nice-to-have?"

While Brodman expects VoiceStream will offer the combined service at a lower price than the two now cost separately, that would likely be for access only. If subscribers wanted seamless hand-off between coverage areas for certain applications, they might have to pay a premium for it, he says.

The appeal of the combined VoiceStream/T-Mobile offering will be limited of course by the number and quality of Wi-Fi hotspots T-Mobile is able to deploy. The deal with Starbucks Corp., which T-Mobile inherited from MobileStar and will see it light up about 70 percent of the company's coffee shop locations "over the next couple of years," is the only expansion plan Brodman can talk about for now.

"We are expanding our airport coverage as well with other [airline] clubs [besides American Airlines], but until the deals get firmed up we can't talk about them," he says. "Our intent is to dominate the public wireless LAN market -- to be the preeminent supplier of wireless hotspots in locations where people want to use this kind of service."

One way VoiceStream and T-Mobile may do this is by partnering with hotspot venue owners. It will definitely do this in Europe, where T-Mobile will probably employ the same strategy it does now on the mobile side: partnering with a country-specific partners to get roaming coverage.

One thing VoiceStream/T-Mobile will almost certainly not do in North America is join forces with aggregators such as Boingo Wireless. It would rather deal directly with the owners of venues to ensure it has more control over quality and customer service.

"That's a model we don't really believe in," Brodman says of Boingo.

How important is combining Wi-Fi and GPRS networks? Is it a breakthrough that could drive increases in subscriber bases on both sides, we asked Brodman, or is it just another arrow in the quiver?

"I'd like to think it's the former," he says. "But it's certainly the latter."

We think so too. So watch for other mobile players to go down the same road.

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