A Tunable OADM (TOADM) is a tunable optical add/drop multiplexer (OADM). It is a component for optical networks that uses tunable filters
.The filters of TOADM multiplexers can be wavelength tuned and allow optical wavelengths to be added and dropped while most channels pass through the TOADM multiplexer without interference. The tunable range includes two wavelengths. Some TOADMs also use tunable passband filters to increase or decrease the channel bandwidth. A TOADM is an alternative to a demultiplexing switch based on a reconfigurable optical add/drop multiplexer.