The reconfiguration in the dense wavelength division multiplexed transmission of 64 channels spaced on 100 GHz channel spacing using digital switches is demonstrated. The system performance has been demonstrated by changing the power of input signal from 0 dBm to -20 dBm and data rate from 20 Gbps to 40 Gbps. Transmission over 180 km distance at 40 Gbps data rate with -10 dBm input power is achieved. The behavior of the system is also analyzed by varying the attenuation from 0 dB to 30 dB of reconfigurable optical add drop multiplexer. The results have been reported for the DWDM system at the 193.1 THz (Ist channel) and 199.5 THz (64 channel) in terms of OSNR, Q-factor and BER.