Banding Together with Laser Clarity
By Jeanie Stokes
from the May 21, 2001 issue of Broadband Week
The fledgling free space optics industry is getting together to promote the use of laser technology for high-speed, high-bandwidth data transmission.
The Free Space Optical (FSO) Alliance, an advocacy group for the emerging fixed wireless sector, plans its first meetings June 26 in Boston during the Wireless Communications Association International's 2001 annual convention. The group's 13 founding members include both service providers and equipment manufacturers.
Using lasers to provide last-mile connectivity has been around on a limited basis for some time, with many applications in place long before the Internet arrived, says Maha Achou, director of advanced technology at San Diego-based Optical Access Inc.
The technology has gotten a fair amount of hype in the past couple of years--aided by the high-profile move last year by former AT&T Wireless CEO Dan Hesse to head FSO equipment and services provider Terabeam Inc.--but the attention also has created some confusion in the marketplace.
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Free Space Optics: Key Players
--fSona Inc., a privately held company based in British Columbia, Canada, relies on FSO receiver technology developed by British Telecom Labs in the U.K. Its first product operates over distances up to 2 km.
--Optical Access Inc. designs, manufactures and provides service using its TereScope(tm) optical wireless links, switches for provisioning and mesh enabling and network management systems.
--Cisco Aironet, a unit of Cisco Network Systems Inc., manufactures optical wireless systems for point-to-point and multipoint deployment, as well as wireless LAN products for both in-building and fixed wireless applications. The series includes a variety of client adapters, access points and line-of-sight wireless bridges.
--Terabeam Inc., the first commercially deployed FSO network in Seattle uses through-the-window lasers to link company local area networks to Terabeam's base stations. It's targeting clients located in Class 2 and 3 office buildings that may not be on major fiber rings in urban areas, and announced plans to deploy in Denver, its second market, this summer.
--AirFiber Inc., a privately held San Diego-based equipment manufacturer, makes a carrier-class FSO networking product designed for incumbent and competitive local exchange carriers.
--LightPointe, also based in San Diego, manufactures carrier class optical wireless transmission systems that can operates at the 850 nm wavelength. It has installed customers in 23 countries.
--Canon U.S.A. Inc., headquartered in Lake Success, N.Y., known for its imaging products such as cameras, lenses and copiers, manufactures the Canobeam line of products initially developed for the broadcasting and communications industries. The Canobeam DT-50 unit claims data speed capabilities of 25 Mbps to 622 Mbps for point-to-point optical data transmission.
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"The biggest challenge is to bring greater awareness of the technology's capabilities and solution to solve the last-mile bottlenecks, both in the public sector and at financial institutions," Achou says. Without that awareness, potential users and potential investors tend now to give the laser technology the same consideration as other last-mile fixed wireless solutions such as local multipoint distribution systems.
"It's not a Star Wars technology. It's a real technology and it works," Achou says.
FSO's reputation, or lack of one, is the industry's biggest hurdle, according to the Strategis Group. Many people don't understand the technology or trust it, and seem surprised when it works.
Strategis, a Washington-based consulting company, estimates the FSO industry is poised to become a strong niche player in the fixed wireless arena, with worldwide equipment revenue projected to grow to about $2 billion in 2005, from less than $100 million in 2000.
FSO equipment currently is being used for a variety of applications, such as last-mile connectivity to buildings, mobile networks assist, network backup and emergency relief. Strategis expects that by 2005, last-mile connectivity will represent two-thirds of the total market.
Most of the 10,000 FSO deployments around the world provide point-to-point connectivity at fiber-like speeds across short distances, such as linking two buildings on a company campus. In those instances, fiber capacity is needed for file transfers, video conferencing and other applications that initially didn't require the networks to be up all the time.
"Now we see it being deployed in metro access networks," by telecommunications carriers, Achou says. "FSO systems are viable solutions for all manner of metro access interconnection using such complementary platforms as fiber, copper, DSL, LMDS and other fixed wireless technologies.
Among the first questions people ask about using laser technology is, 'Is it safe?' Achou says. Today's technology largely relies on the 800 and 1550 nanometer wavelengths, and generally meet eye safety requirements set out by ANSI and IEC Class 1 laser classifications.
The alliance can help both lay people and the industry as a whole understand about eye safety issues and new laser classifications, says Steve Mecherle, chief technical officer at fSona Inc.
"There are some vendors selling equipment that is not eye safe," and government laser labeling standards, even in the United States, aren't necessarily up to date, says Mecherle, who serves on the alliance's initial board of directors.
The 1550 nm gear can provide bandwidth comparable to that of wired switches ranging from OC-3 to OC-24. It is more expensive to deploy than lower wavelengths.
The laser links can be deployed from rooftop to rooftop, or as in the case of Seattle-based Terabeam, through the window, to a service provider's base station. There it can interface with a variety of telecom technologies, including SONET, ATM and metro fiber rings.
The major drawback to FSO technology is fog, which, if dense enough, can render a system unusable. "That's why we keep the distances very short, under 200 meters in most cases," says Steve Bloom, chief technology officer at AirFiber Inc.
That's also one of the areas where questions have been raised regarding some companies' claims about the potential distances they can cover without a reliable backup based on fiber or microwave. Bloom says some of the early adopters stretched their ranges, although some have since backed away from early claims.
Enhancements that are being studied include mesh technology, a multipoint-to-multipoint deployment. Mesh provides more survivability and redundancy from a network point of view and can provide the backup needed to ensure carrier reliability, Achou and Bloom say.
One of the industry's biggest selling points is the speed at which it can be deployed. Because no licensed spectrum is involved, FSO literally can provide "buy today, install tomorrow" connectivity.
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