Wireless Today and Tomorrow

FRAMINGHAM (07/31/2000) - The freedom promised by wireless networks - computing wherever you roam - is so compelling that the technology has remained a hot topic, even though few organizations are actually using it. In 1997, Johns Hopkins University's School of Public Health (SPH) became one of those few.

What began as a wireless LAN pilot with 40 students has grown to 500 students today, fueled by the SPH's cash rebate program for students who buy laptops and another program for lending wireless LAN PC Cards.

"Of 600 new students [who will enroll this fall], half will either buy laptops or bring them with them," says Ross A. McKenzie, the SPH's information systems director. "By the time they leave, 80% will have them."

So, this summer, the school will upgrade its wireless LAN to the faster 802.11b Direct Sequence Spread Spectrum (DSSS) standard that was released last year, McKenzie says.

In 1995, the Baltimore-based university was facing "a forklift upgrade of all its wiring at a cost of about $2.5 million," says J. P. Garvin, the SPH's assistant IS director.

"Professors wanted to bring computing into the classrooms, which weren't then wired," he says.

"The school's dean also wanted to encourage students to get laptops," says McKenzie. "He feels they're important analytical and collaborative tools for public health officials.

"About 30% of our students are from foreign countries," McKenzie continues.

"When they leave here, they go home to become the ministers of health for their region or country. They need the laptops for data-analysis tools and statistical-analysis tools."

The Costs of Wires

But upgrading the school's Ethernet LAN was going to be expensive, he says.

Wiring the university's 80-year-old buildings would have required putting in a false floor at a cost of $10,000 per classroom. Including wiring costs, a conventional LAN would have cost $18,000 per classroom, McKenzie says. Wiring areas such as the cafeteria, with its huge expanse of windows, would have been impossible, Garvin adds.

The idea for the school's first wireless LAN was serendipitous, McKenzie says.

On a visit to Texas Instruments Inc. in Dallas to evaluate laptops, he noticed lights on TI's staff laptops. "It was wireless LAN cards," he says.

By spring of 1997, the SPH had a pilot with 40 of its students. Information technology staff installed wireless LAN cards in the laptops and at access points in strategic sites at the SPH.

After a month, the pilot was being hailed as a success, but as a test, 20 students stressed the system by simultaneously downloading a 10MB file from an external Web site. All were able to download the file within five minutes.

A wireless LAN requires two access points per classroom, each of which includes a radio transceiver, 10Base-T port and encryption software. The access points connect to a hub on the Ethernet LAN.

The cost would be $3,000 per classroom - $15,000 less than for a conventional LAN, McKenzie says.

"When cabling is already deployed, DSSS [wireless] still costs about three times more," says Stan Schatt, an analyst at Giga Information Group Inc. in Dallas. But for such "green-field type implementations, the [Wireless LAN Association in Willoughby, Ohio] claims the payback is less than year."

Where historic building status or asbestos in walls precludes drilling to wire for a conventional LAN, wireless is virtually mandatory, says Patrick Dryden, an analyst at Illuminata Inc. in Nashua, N.H.

Plus, Dryden adds, "the freedom to move desktops easily is a dream for users, business groups, building managers and IT managers."

The SPH concurred, says Garvin, "So we developed a three-year implementation plan."

"But our dean was so enamored of the idea, he told us to do it in six months," McKenzie says. "It was a little scary - there was no standard yet."

Over the next six months, the SPH installed nearly 100 access points throughout the campus and upgraded to IEEE 802.11 when the hardware became available in 1998.

The 802.11 standard includes Frequency Hopping Spread Spectrum (FHSS) signaling. Data travels on blocks that hop from one frequency to another every tenth of a second in a pseudorandom pattern known only to the sender and receiver.

DSSS signaling uses a broadband carrier and generates a bit pattern, or chip, for each bit of data. Each bit of data is identified, so the receiver can easily pick the data out of background noise.

Throughput speed for the new LAN will be greater. The FHSS data rate is 2M bit/sec., while DSSS signals transmit at a theoretical 11M bit/sec., although distance and physical blockages affect the rate.

Wireless has delivered on its promise at the SPH, Garvin says.

Chip Richter, a student in the SPH's distance learning program, agrees. "I see people using it all over campus to collaborate on projects and do research or use some of the analysis software" that the SPH loads on student laptops. "It's not just for e-mail and Internet access and taking notes," he adds. wAnd TomorrowWhile comedians joke about "smart" refrigerators and televisions duking it out for control of the cellular phone, smart soft-drink machines are already practicing going online wirelessly to report data that will save money for soft-drink vendors.

Dr Pepper/Seven Up Inc. in Plano, Texas, is a few weeks into a pilot in which a dozen vending machines are keeping Rick Harris, manager of channel research at Dr Pepper, apprised of how sales are going.

"For the first time, we're getting real data rather than ballpark figures on exactly what's going through those vending machines," Harris says.

The company owns 17 brands and franchises bottling territories for each, a Dr Pepper spokesman says. Tracking sales of a single brand at different locations and for different demographic profiles has been impossible, Harris says. Data is collected, he says, but it's "inconsistent from bottler to bottler."

Pilot Installation

For the pilot, Dr Pepper is using VendCast software, hardware and services from Isochron Data Corp. in Austin, Texas. Dr Pepper uses the VendCast sales and operations module. Other modules include dispatch, which is used for truck routing; cash accounting; and maintenance.

Isochron installs VendCast hardware - which includes its own software - and a Motorola Inc. ReFlex protocol two-way paging device in each vending machine.

Harris says installation takes about 12 minutes and costs $340, while monitoring is $6.50 per month.

VendCast software collects inventory, sales and machine-health data via a connection to the machine's serial port.

Two-way paging lets signals shift between simulcast and local mode, or multi- and single-channel broadcasting, allowing immediate signal and response between vending machines and Isochron's Network Operations Center (NOC).

VendCast servers at the NOC typically poll vending machines daily, says Aruni Gunasegaram, president and co-founder of Isochron. A dome antenna atop the vending machine allows broadcast and reception in the 900-MHz frequency via the narrowband personal communications services wireless network run by Jackson, Miss.-based SkyTel Communications Inc. In sites with several machines, all report to a central unit, from which all data is sent, Harris says.

Isochron aggregates the data and stores it at the NOC. On PCs with VendCast client software installed, users go to personalized Web sites and use browsers to access their data, which is secured by 56-bit Secure Sockets Layer encryption from VeriSign Inc. in Mountain View Calif., Gunasegaram says. Users can query their data, view preconfigured reports and generate new reports. They can also download data for import into their own applications, she adds.

Isochron's similar PolarCast system is in use by bagged ice vendors, Gunasegaram says. When internal machine temperatures rise, the ice machine generates an alarm to summon an attendant.

"I wouldn't be surprised to see service providers offering" such process-control applications as a service, says Stan Schatt, an analyst at Giga Information Group Inc. in Cambridge, Mass. "A black box at a site could periodically poll devices via Bluetooth [a wireless connectivity technology] and then forward the data under secure conditions to a data center, where the reports are generated."

However, use of such services over telecommunications networks adds new requirements, says Pedro Fernandez, senior vice president of corporate strategy and marketing at Concero Inc. in Austin, Texas.

New Requirements

When Concero helped build a similar implementation, using Reston, Va.-based Nextel Communications Inc.'s wireless network, the company found that "Nextel has its requirements that you have to meet," Fernandez says. "You can't be generating a million hits an hour. You have to architect a wireless application differently, and that application has to be Nextel-certified."

One benefit of the service is that it avoids adding management chores and communications traffic to existing networks, Harris says.

Such savings may be minimal, says Patrick Dryden, an analyst at consultancy Illuminata Inc. in Nashua, N.H.

Dryden says the anticipated burden is a common misconception. IT managers "think of vending machines, truck fleets and washing machines as PCs," he says.

"The idea of taking on the support burden for a few hundred thousand additional PCs is frightening. Yet embedded systems aren't anywhere near as cantankerous as PCs; they lack the flexibility and the users, so [there are] no surprises."

Harris says that what is unquestionable is the business value of such data, both in daily operations and in the potential for data mining. Dr Pepper will use the data in "several ongoing research projects," he adds.

"Information like this is a great asset to have to consider new placements of vending machines, or locations where multivendor machines might be warranted, such as in front of a Wal-Mart or high-traffic supermarket," Harris says.

A machine operator can use the data "to plan loading of trucks and truck routes. Ideally, he'd like to spend his time filling an 80% empty machine rather than one that's maybe only 30% depleted," he says.

Savings from such systems "will far outweigh their costs," says Callie Nelsen, an analyst at International Data Corp. in Framingham, Mass. Even a small savings can be significant, she adds. For the vending channel, profit margins of 14% to 15% are common. Dr Pepper brings in 19%, Harris says.

Consumers will interact more with the vending machines, Nelsen says. "You can already buy a [soft drink] from a vending machine in Finland with your cell phone," she says. "It'll take a while here - the country is more spread out, and we're behind Europe in use of cell phones."

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