Bandwidth9 Scores a Coup
The demo shows how low-cost tunable lasers can enable service providers to set up and tear down wavelengths on demand in metro networks, from a remote control panel. This promises to slash provisioning times and eliminate truck rolls -- having to send craftsmen into the field to reconfigure equipment manually.
The key words here are "low cost." The idea won’t fly in metro networks unless tunable lasers cost more or less the same as the fixed wavelength lasers used in current metro equipment. And that’s where Bandwidth9 comes in.
Bandwidth9 has a particularly low-cost tunable laser for metro applications. In a nutshell, it’s taken a laser technology that’s already stolen the market for 850 nanometer, short-range fiber optics –- vertical cavity surface emitting lasers (VCSELs) -- and found a way of making it work at 1550 nanometers, the wavelength used in telecom networks (see Bandwidth9 Claims Laser Breakthrough).
Bandwidth9 says that its VCSEL will cost about the same as a fixed-wavelength distributed feedback laser (DFB) and gives three reasons for managing to get the price down to that level.
First, VCSELs are intrinsically low cost because light comes out of them vertically, so they can be tested while they’re still on a wafer. This means that duds can be weeded out early on, before a lot more money is spent on packaging for them (see Laser Blazers).
Second, Bandwidth9’s lasers can be directly modulated. There’s no need for a separate modulator to interrupt the beam of light coming out of the VCSEL to create the stream of light pulses that carry data.
Third, Bandwidth9 plans to make its VCSELs in very large volumes. While it’s been developing the laser itself it’s also been developing the process for making them. It’s built a facility with "very substantial capacity -- tens of thousands of devices a month," says Tim Richardson, Bandwidth9’s executive vice president, business development.
Other startups -- notably Agility Communications Inc. -- make similar claims for other types of laser. Agility is developing a side emitting laser (a form of distributed Bragg grating -- see Tune In!) and says that it can also bring costs down to those of today’s fixed wavelength lasers. It’s also aiming to make an integrated laser and modulator and is building a high-capacity production plant.
Nortel, however, says it’s sold on tunable VCSELs becoming the predominant laser technology in telecom equipment. That’s why it acquired another tunable VCSEL startup, Coretek, last year (see Nortel Gambles $1.43 Billion On Tunable Lasers). Coretek’s tunable VCSEL targets a different market than Bandwidth9’s. It’s much more powerful and much more expensive and is a key part of Nortel’s plans to deliver 40-gig long-haul transmission equipment.
Bandwidth9’s tunable laser pumps out around 100 microwatts of power and switches from one wavelength to another in 200 microseconds, according to Richardson. In the Supercomm demo, it was being used to switch among 11 wavelengths.
“It’s a very low-cost solution for metro access,” according to Peter Evans, vice president of marketing in Nortel’s metro optical division. Evans expects tunable VCSELs like Bandwidth9’s to become “a standard offering” in Nortel’s metro platform.
- Peter Heywood, Founding Editor, Light Reading
http://www.lightreading.comFor more information on Supercomm 2001, please visit the Light Reading Supercomm 2001 Site.