An optical network monitor and a method for monitoring the optical signals of an optical network including a spectrograph that includes a detector array, a processor and outputs. The network monitor receives an optical input signal which includes individual channels. The optical signal is transmitted onto the spectrograph which disperses the optical signal into the individual channels. The individual channels are directed onto the detector array so that the channels are spaced across the detector array. The detector array detects the channels in parallel and transmits to the processor channel parameter data which is processes the parameter data through internal algorithms to produce the outputs.