This article is the eighth in a series of 10 stories we're running over two weeks, covering today's most significant (and just plain cool) emerging technologies. It's part of our annual "10 Emerging Technologies" report, which appears in the March/April print issue of Technology Review.

In New Brunswick, NJ, is a large, white room with an army of yellow boxes hanging from the ceiling. Eight hundred in all, the boxes are actually a unique grid of radios that lets researchers design and test ways to link mobile, radio-equipped computers in configurations that can change on the fly.

The ability to form such ad hoc networks, says Dipankar Raychaudhuri, director of the Rutgers University lab that houses the radios, will be critical to the advent of pervasive computing--in which everything from your car to your coffee cup "talks" to other devices in an attempt to make your life run more smoothly.

Wireless transactions already take place; anybody who speeds through tolls with an E-ZPass transmitter participates in them daily. But Raychaudhuri foresees a not-too-distant day when radio frequency identification (RFID) tags embedded in merchandise call your cell phone to alert you to sales, cars talk to each other to avoid collisions, and elderly people carry heart and blood-pressure monitors that can call a doctor during a medical emergency. Even mesh networks, collections of wireless devices that pass data one to another until it reaches a central computer, may need to be connected to pagers, cell phones, or other gadgets that employ diverse wireless protocols.

Hundreds of researchers at universities, large companies such as Microsoft, Intel, and Nortel, and small startups are developing embedded radio devices and sensors. But making computing truly pervasive entails tying these disparate pieces together, says Raychaudhuri, a professor of electrical and computer engineering at Rutgers. Finding ways to do that is what the radio test grid, which Raychaudhuri built with computer scientists Ivan Seskar and Max Ott, is for.

One problem the researchers are addressing is that different devices communicate using different radio standards: RFID tags use one set of standards, cell phones still others, and various Wi-Fi devices several versions of a third. Linking such devices into a pervasive network means providing them with a common protocol.

Take, for example, the issue of automotive safety. Enabling cars to communicate with each other could prevent crashes; in Raychaudhuri's vision, each car would have a Global Positioning System unit and send its exact location to nearby vehicles. But realizing that vision requires a protocol that allows the cars not only to communicate but also to decide how many other cars they should include in their networks and how close another car should be to be included. As programmers develop candidates for such a protocol, they try them out on the radio test bed. Each yellow box contains a computer and three different radios, two for handling the various Wi-Fi standards and one that uses either Bluetooth or ZigBee, short-range wireless protocols for personal electronics and for monitoring or control devices, respectively. The researchers configure the radios to mimic the situation they want to test and load their protocols to see, for instance, how long it takes each radio to detect neighbors and send data. "If I want cars not to collide, it cannot take 10 seconds to determine that a car is nearby," says Raychaudhuri. "It has to take a few microseconds."

The Rutgers radio grid is the first large-scale shared research facility that researchers can use to study multiple wireless devices and network technologies. "The sort of real-world complexity, dealing with real-world numbers that [the test bed] allows you to do, is something that really makes it quite unique," says Tod Sizer, director of the Wireless Technology Research Department at Lucent Technologies' Bell Labs.

Sizer's group is working with Raychaudhuri to build cognitive-radio boxes that can be programmed to employ a wide variety of wireless standards, such as RFID, Wi-Fi, or cellular-phone protocols.

While hordes of researchers are developing new networked devices, Raychaudhuri says it is the standardization of communications protocols that will make pervasive computing take off. In just five years, he believes, networks of embedded devices will be all around us. His aim is to reduce "friction" in daily life, eliminating lines, saving time in searching for objects, automating security checkpoints in airports, and the like. "You save 10 seconds here, two minutes there, but it's significant," he says. He claims that just a 2 percent reduction of friction in the world's economy could be worth hundreds of billions of dollars in productivity. "Each transaction is small, but the benefit to society is very large."

OTHER PLAYERS
Pervasive Wireless

David Culler -- Operating systems and middleware for wireless sensors
University of California, Berkeley

Kazuo Imai -- Integrating cellular with other network technology
NTT DoCoMo, Tokyo, Japan

Lakshman Krishnamurthy and Steven Conner -- Wireless network architecture
Intel, Santa Clara, CA

Home page image courtesy of Steve Moors.