ince the invention of 40Gbit/s port routers and the rapidly growing demand for the bandwith of transmission
the DWDM based on 40Gbit/s will be widely used gradually.This article brifely discusses the essential technical factors of 80×40Gb/s DWDM and its impacts on the operations and maintenance of legacy networks in the 80×40Gb/s trial commercial project of China Mobile.