I also don't understand how they get 400Gig. 80 channels * 2.5Gig/channel = 200Gig. It seems they have been working on this for 18 months.
Lucent Cracks The Terabit Network Barrier
(01/28/98; 10:34 a.m. EST)
By Chappell Brown, EE Times Lucent Technologies is introducing a refined version of its optical WDM technology it says will let network builders achieve terabit-per-second transmission rates.
A single-platform system, WaveStar OLS400G, can multiplex 400 gigabits of data onto a single standard fiber. The platform lets network designers incrementally add fibers, up to a maximum of eight, for a total capacity of 3.2 Tbits. With delivery scheduled for the fourth quarter, AT&T has signed on as the first customer and is serving as a beta-test site for the system.
"With network traffic increasing at around 80 percent a year, this new capability is positioned to handle projected industry growth," said Harry Bosco, chief operating officer for Lucent's Optical Networking Group. Bosco said WaveStar has been on a fast-track development program at Bell Laboratories for the past 18 months, and the new level of performance resulted from improvements in the previous dense WDM (DWDM) technology the company has been marketing. To illustrate the leap in capability, Bosco said a single fiber can now carry the entire traffic load of the Internet with the new multiplexing system.
DWDM uses planar optical waveguides modulated with a laser to multiplex data onto different wavelengths. The technique has caught on with optical-network system vendors, since the multiplexing capability can be added at either end of an installed fiber to increase its capacity. The higher capacity achieved with WaveStar resulted from a number of refinements including a better wide-band optical amplifier, automatic gain control, and forward error correction. That allowed Bell Labs engineers to halve the frequency spacing between neighboring wavelengths. The combined improvements allowed the team to put 80 2.5-gigabit-per-second channels onto a single fiber, five times the capacity of existing DWDM systems. The company has dubbed the improved capability ultra-dense wavelength division multiplexing, or UWDM.
In addition to raw throughput, another design objective was flexibility, Bosco said. The platform "gives us tremendous flexibility in adding capacity," he said.
WaveStar is the first high-capacity switch to support both OC-48 and OC-192 equipment from a variety of vendors, Bosco said. That required a single multiplexing system to handle two different data rates -- 2.5 Gbps for OC-48 and 10 Gbps for OC-192. To offer better unit-cost efficiency for customers, the system also lets designers add bandwidth incrementally. Channels can be added two at a time up to a maximum of 80.
The system also offers full add-drop capability. Because of the flexibility, even small network operations can get into the UDWDM game with a minimal configuration and the capability to add as business expands. Lucent said it estimates the flexibility alone could save up to 40 percent in equipment costs.
techweb.com
PS. Can they pump 200Gig in either end giving the capability of a single fiber supporting 400Gig? The 80 channels going in two directions shouldn't interact,... it's light.... until later. |
