An add/drop multiplexer node in an optical network comprises an optical channel-selective switch. The switch is operable in bar and cross states and has a first input for the reception of optical multiplexed channels, a second input connected to an output on a line terminal associated with the node for...http://www.google.fr/patents/US6134036?utm_source=gb-gplus-shareBrevet US6134036 - Add/drop multiplexer node
