Lucent Pushes Optical Networks Into The Light
Date: 3/4/98
Author: Michele Hostetler
Data networks soon could be moving the equivalent of more than 90,000 sets of encyclopedias per second, thanks to a new optical technology that speeds data over light.
Lucent Technologies Inc. is pioneering a method of making better use of existing, as well as new, fiber-optic lines. Analysts say sales of fiber-optic networks for data could reach $1.8 billion this year, from zero as recently as '95.
Optics promise to boost bandwidth, which is needed as networks transport more complex data. Instead of sending data over normal copper wires, optical data go over fiber, or glass, lines.
Some telecom companies have been building new fiber-optic networks, or improving old ones, because more customers need speedy communication.
Lucent, a telecom leader, wants to use optics as its entry into the high-end data networking field. At the same time, networking leaders such as Cisco Systems Inc. now are making voice products. And that's sparking more competition between networking and telecom companies.
Lucent's optical network is slated to get its first test this fall. The customer is its former parent, AT&T Corp., which finds itself competing with the new era of fiber networks.
An optical network can move 400 gigabits of information a second. By contrast, gigabit Ethernet, the fastest of mainstream data networking technology, plods along at one gigabit per second. A gigabit is one billion bits.
Murray Hill, N.J.-based Lucent envisions a quick surge in this market, says Kathy Szelag, director of strategy for Lucent's Optical Networking unit.
''This technology will take off really fast, almost as fast as Cabbage Patch dolls,'' she said.
Optical networks can more speedily connect branch offices to company headquarters or link far-flung networks.
Telecommunications carriers and Internet service providers are eyeing optics as a way to ship data faster, says Harry Bosco, chief operating officer of Lucent's Optical Networking business.
''I would say that any smart carrier today is putting in optical networks,'' Bosco said.
Optical data networks can run on the fiber-optic telephone lines already in place. With optical networks, data rides on streams of light.
Until recently, fiber-optic lines could only move voice or data traffic at 10 gigabits a second, and only over a maximum of eight wavelengths per line. To send more data, the only option was laying more fiber-optic cable, Bosco says. And that's costly.
But a new technology came out of Lucent's labs in '95 to give optical networks a boost. The technology is called dense wavelength division multiplexers.
DWDMs act like prisms to increase the number of light streams upon which data can ride. When a single laser light passes through a DWDM, it splits into 10 light streams. So now the maximum number of wavelengths carrying data jumps from eight to 80.
DWDMs serve another purpose. Keeping signals strong over long distances - amplification - is a key to optical networks.
When a signal or data stream is routed across the country, it passes through a switching station. These are connection points, or routing points, for voice and data traffic. But the switch has to translate the light signal into an electrical signal in order to pass it on through. The data then have to be reconverted to light.
But DWDMs keep the data stream in light form. Data doesn't have to be converted into electrical signals. And this saves time. There's no need to switch back and forth between optical and electrical signals.
Optical networks also can connect to other networking technologies like Ethernet or asynchronous transfer mode (ATM) with a simple adapter card, Szelag says. An adapter card connects computers to a network.
Fiber- optic networks will become better and more popular, says Peter Bernstein, president of Infonautics Consulting Inc. in Ramsey, N.J. ATM and the Internet's language - called Internet protocol, or IP - already work with fiber-optic networks, he says.
''It all is, in essence, really complementary,'' Bernstein said.
But optical networks have a ways to go before they become commonplace, he says. The technology still is more costly, and existing technology is improving.
''I think the grand vision with all technology is that it tends to be evolutionary rather than revolutionary,'' Bernstein said.
Optics are making inroads at the network's core, or backbone, where extra boosts are needed to handle intense traffic, says Lucent's Bosco.
Bosco likens the transition to when digital technology burst onto the scene. It slowly made its way to personal computers and other consumer devices. |
