Why are so many service channel wavelengths needed?
A. In a given WDM system, there is only one type of service channel laser needed. As the WDM application is relatively new, there has not been a standard governing this aspect of the system. The ITU’s latest recommendation is to use 1510 nm lasers. In the market today there are at least three other known wavelengths. They are: 1625 nm, 1420 nm and 1410 nm lasers. For definitions of terms used herein, please visit the glossary.
