The FRM301 is a standard 3U, 19 inch rack mountable, Platform Media Converter that features 16 line card capacities. Currently supported line cards include Ethernet to fiber converters for 10/100Base-TX, or 10/100/1000Base-TX over multimode fiber (up to 2 km), single mode fiber (up to 120 km) or utilizing WDM (up to 40 km). WDM (Wave Division Multiplexing) converts each input-output data stream into separate wavelengths of light and transmits/receives these channels through the same optical fiber. Besides, FRM301 line cards can also support G.703 E1/T1, Datacom (V35, X.21, RS530/ 449/ 232) and Serial (RS485/ 422/ 232) data communication interfaces over fiber.