the DWDM system would be limited by the transmission impairments that caused by attenuation
CD
PMD and nonlinear effects.There is an urgent need for more advanced technology to reduce the impact of these transmission impairments
so as to solve the systemrate and the transmission distance is limited by the problemes.This paper mainly introduces the current developing condition and key technique of 100G DWDM
and makes some suggestions for future strategy to carry out.