said by ronpin :

We should say practically unlimited. uDWDM (u= "ultra") is currently projected at up to 1024 lambda's. Currently each of those lambda's can use standard equipment to get 10gbs on each lambda. You do the math.

uDWDM is not in common use -- yet.

said by whizkid3 :



We will assume the fiber can transmit all visible light without any breaks in the spectrum

Since we know that fiber optics can transmit infra-red and ultra violet light, the question becomes where does one draw the line at the bandwidth? Lets assume we can transmit all ultra-violet, visible and infrared light.

said by somitho :

It isn't? SouthernCross and Apollo are the two largest uDWDM networks for undersea cable

The contract is for Alcatel to equip the third fiber pair in the Southern Cross network with 10 gigabits per second (Gbps) capacity per wavelength. Alcatel will supply undersea line Dense Wavelength Division Multiplexing (DWDM) terminals and terrestrial Synchronous Digital Hierarchy (SDH) equipment - both operating at 10 Gbps.

The upgrade of the Southern Cross Cable Network is made possible by using Alcatel super FEC (Forward Error Correction) technology for undersea terminals, officials said. Super FEC can supervise and correct detected errors of the signal transmission along the system for larger transmission bands than 2.5 Gbps. This makes it possible to send wavelengths operating at 10 Gbps over submersible cable and repeaters designed to operate at 2.5 Gbps.

The network also will benefit from multiplexers dedicated for high-speed and fully secured core transport systems with the Alcatel 10 Gbps multi-service node. Due to its non-blocking and powerful architecture, this system allows the choice of the most suitable network configuration for evolving network requirements as well as cost reduction and enhanced service quality.

The contract covers two phases. The first involves adding 50 Gbps (5x10 Gbps) to the initial total network capacity of 80 Gbps. The second phase will add a further 110 Gbps of capacity (11x10 Gbps) to reach a total of 240 Gbps of fully protected capacity. The two phases are expected to be completed by early 2003.

Bell Labs Scientists Push the Boundaries of Optical Networking Capabilities
Scientists from Bell Labs, the research and development arm of Lucent Technologies, have demonstrated two optical networking feats at this year’s analyst conference at its Murray Hill headquarters. On the display floor, Bell Labs researchers demonstrated a method whereby information at the rate of 160 Gbps over optical fiber using a single wavelength and plans to expand the system by using DWDM The 160 Gbps single-channel transmission demonstration was done over 300 km of Lucent's TrueWave RS fiber.
Second, the researchers demonstrated the transmission of 1,022 wavelengths over a single fiber. Perhaps the most compelling aspect of the demonstration was the experimental transmitter used a single ultra-high-speed laser to generate signals over all 1,022 wavelengths, instead of using a separate laser for each, as is done in conventional multi-wavelength systems.
Today's commercial optical systems combine up to 100 wavelengths on an optical fiber, using DWDM. Conventionally, DWDM signals are separate by 50 GHz frequency spacing, but the 1,022-channel system operates at a record high density of 10 GHz channel spacing. Each channel occupies only 10 GHz of frequency bandwidth, making this an ultra-dense WDM (UDWDM) transmitter.
The 1,022-channel transmitter carries information at the rate of 37 Mbps of information, for a total system capacity of more than 37 Gbps. The researchers believe the system can be scaled up to OC-48 data rates, for a capacity of several Tbps. The team broke its own world record, the 1997 demonstration of a similar transmitter with 206 independent channels. Researchers plan further expansion of system capacity and density, and expect to use the new transmitter in novel data-networking applications.