Technique for detecting noise on a data channel

摘要: A communications network has a plurality of nodes interconnected by an optical transmission medium. The medium is capable carrying wavelengths organized into bands. filter at each node for drops band associated therewith and passively forwards other bands through the device provided adding to Communication can be established directly between pair in sharing common without active intervention any intervening node. This allows protocol independent. Also, low losses incurred passive filters permit relatively long path lengths amplification.