DWDM Mux Demux is usually used for long-haul transmission where wavelengths are packed tightly together over the C-band, up to 48 wavelengths in 100GHz grid(0.8nm) and 96 wavelengths in 50GHz grid(0.4nm). It’s protocol transparent and suit applications including 10/1G Ethernet, SDH/SONET, 16/8/4/2/1G Fibre Channel, FTTx and CATV.