Two breakthrough optical networking technologies that use laser beams to transmit digital information could dramatically boost the capacity of school networks as early as next year.

Lucent Technologies’ new WaveStar OpticAir system will use state-of-the-art lasers, amplifiers, and receivers that can be placed on school rooftops or in windows to transmit voice, video, and data from point to point through the air.

According to Lucent, the system eventually will be able to transmit up to 10 gigabits (billion bits) of information per second wirelessly between points. That’s the equivalent of 15 CD-ROMs each second, or 65 times more information than with today’s wireless radio frequencies, Lucent said.

Meanwhile, researchers at San Diego State University have developed a different technology, called Refractive Synchronization Communication, that allows a single-wavelength laser beam to carry many signals on a fiber optic cable.

The simplicity of the single wavelength allows for a much higher bandwidth transmission at less cost than those reached through traditional multiple wavelength technology, according to representatives of the patent holder, a San Diego company called SilkRoad Inc.

Fiber optics—without the fiber

Lucent’s wireless laser technology, which the company described as about 99 percent reliable now, will be field-tested by the Bermuda-based optical networking company Global Crossing in December. By March, Lucent plans to roll out an initial version of the service to customers.

“If our testing of the product meets expectations, it could offer a breakthrough method to help our global customers bypass local bottlenecks,” said Wally Dawson, a senior vice president of Global Crossing, which is building an international fiber optic network. “Based on projections, no one else is even approaching the amount of bandwidth” that the technology will bring to the market.

To work right, there has to be a clear line of sight between stations. The system also has a limited range; transmissions work best between distances of less than 5 kilometers. But despite these limitations, the technology has great potential as a “last mile” access solution for applications that require increased bandwidth or for delivering high-speed connections between neighboring school buildings, said Lucent spokeswoman Mary Ward.

“I think it’s going to be one of those things where as people think about the technology, they’ll come up with more and more applications,” Ward said. “It’s going to open a lot of possibilities.”

Designed by Bell Labs, the WaveStar OpticAir system will use “expanded-beam” lasers to free optical networking from the confines of fiber cables. The laser beams, which Lucent says will not pose any environmental risk, can be expanded to a width of about 2 meters and will not be visible to the naked eye.

As in fiber optics, the system will use the photons in pulses of light to transmit information digitally. Lucent says its system will be able to reach speeds as high as 10 Gbps by using a technology known as dense wave division multiplexing (DWDM), which splits the beams of light into different wavelengths, or colors, to create more channels for carrying information.

The system will consist of two terminal units that are used to transmit and receive the signals. Each unit will be about the size of a mailbox and will include optical translators, so they can be deployed easily within existing networks.

Unlike wireless radio frequencies, the WaveStar OpticAir system doesn’t require a licensing of spectrums, Ward said, because the streams of photons do not interfere with each other.

With its limitations of range, the technology isn’t meant to replace fiber-optic lines. But it could be a popular alternative for networking school campuses—especially in places where running a land-based fiber line would be impractical, said Gerry Butters, president of Lucent’s optical networking group.

“Lucent soon will be able to provide the power of fiber optics just about anywhere—with or without the fiber,” he said.

Because its transmission system is portable, the technology also could make an ideal solution for broadcasting special events, Ward said. For example, the OpticAir system could be set up to transmit video of a guest lecturer from one school to the others within a district, she said.

The first release of Lucent’s WaveStar OpticAir system, which will support one wavelength at speeds up to 2.5 Gbps, is expected to be commercially available by March. A four-wavelength system with a maximum capacity of 10 Gbps is expected to be available next summer.

The company didn’t provide details about how much the technology would cost, other than to say it would be comparable to the cost of installing current high-speed fiber lines.

Single-wavelength beams

Silkroad is a company with only 75 employees. But with its Refractive Synchronization Communication technology, the firm hopes one day to compete with the major producers of fiber cable technology such as Lucent and Nortel.

“The phone company of the future isn’t a phone company, it’s a bandwidth company,” Jeffery Kagan, an Atlanta-based telecommunication analyst, told The San Diego Union Tribune. “Data on the network is growing at several hundred percent per year. We have to find a way to squeeze more out of the network we have. This will unleash the power of the digital future.”

San Diego State’s researchers reportedly found that SilkRoad’s system was able to send a 411 megabyte file of 3D geological visualization data from one computer on campus to another in 8.21 seconds with 0 percent packet loss. A standard connection would have taken almost an hour to transmit the same amount of information, the company said.

According to SilkRoad representatives, San Diego State will be using this new technology in its own facilities to further the university’s international distance learning program.

In one demonstration, SilkRoad reportedly transmitted 93 billion bits of information per second—the equivalent of 77,500 copies of Moby Dick—through a single wavelength of fiber optic cable.

The first commercial application of SilkRoad’s new product line is currently undergoing field testing under the name Emissary 1000. It is expected to be on the market by the first quarter of 2000, company representatives said.

One important aspect of the new technology is that it reportedly allows transmission of video without the significant image lag that often occurs now. The new laser technology reportedly handles large file transfers, increases network speed and capacity, and supports a variety of network security methods. Pricing has yet to be established on the Emissary line.

Although the technology is expected to be adopted almost immediately by colleges and universities, Kris Stewart, computer science professor and director of the EdCenter at San Diego State, has some reservations about how soon it will be available for K-12 computer systems.

“I’m not sure if individual schools currently have the level of support they need to keep a high-level system [such as Emissary 1000] up. It’s a huge commitment. But it would be a great benefit for K-12 to be able to achieve faster connections if they had the infrastructure to support it.”

Representatives of SilkRoad Inc. argue that the benefits of their product outweigh the potential start-up costs and investment in training personnel at the K-12 level. Mike Emerson of SilkRoad Inc. told eSchool News that his company’s bandwidth-boosting technology would improve schools’ ability “to be connected over a network and broadcast interactive classes over a wide area.”

Added Emerson: “What’s available right now is very slow, and the picture is often blurred or fuzzy. What we offer is a full screen where everyone is operating in real time.” Full-screen transmissions without any image lag would be ideal for distance learning applications, Emerson indicated.

Lucent Technologies

SilkRoad Inc.

Global Crossing

The San Diego Union Tribune

EdCenter at San Diego State University