Patent ID: 8204374
Filing Date: 2012-06-19
Classification: H04J

Abstract:
1. An optical network for transmitting information, said optical network comprising: an optical ring including a plurality of nodes and at least two fibers interconnecting said plurality of nodes during normal operation of said optical ring; each of said at least two fibers having a plurality of channels divided among working channels and protection channels; said working channels carry working traffic when no failures are present in said optical ring, said protection channels carry working traffic when there is a failure in a corresponding working channel; and at least one of said plurality of nodes having a reconfigurable add/drop multiplexer permitting wavelengths to be added, dropped and expressed from a location remote from the location of said at least one of said plurality of nodes; said reconfigurable add/drop multiplexer comprising a reconfigurable blocking filter for selectively adding/dropping a channel by remote configuration; said remote configuration comprising reconfiguration of the reconfigurable add/drop multiplexer from a remote site by configuring the reconfigurable blocking filter; wherein said reconfigurable blocking filter is initially set to express protection channels; wherein, responsive to said reconfigurable blocking filter initially set to express protection channels, one or more of the plurality of nodes selectively attenuates one or more pass through channels using a reconfigurable blocking filter in blocking mode at the one or more of the plurality of nodes in order to mitigate re-circulating amplified spontaneous emission caused by the express protection channels through said reconfigurable blocking filter; wherein said plurality of nodes includes a source node, a sink node and an intermediate node, at least one of said source node, said sink node and said intermediate node has at least one reconfigurable blocking filter for blocking a first type of traffic and expressing a second type of traffic; and wherein at least one of said source node, said intermediate node and said sink node includes a single transceiver and means for selectively connecting said single transceiver to said working channels and said protection channels for providing optical shared protection to said single transceiver.