Optical line switching system

Claim 2

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the working and protection optical fibers are respectively independently paired such that only two unit optical switches are required for each pair of the working and protection optical fibers to independently implement the optical protection scheme.

Claim 3

An optical line switching system according to claim 1 , further comprising an optical signal processing device coupled to the optical switch and configured to perform adding/dropping and multiplexing/demultiplexing of the optical signals.

Claim 4

An optical line switching system according to claim 1 , wherein the optical protection scheme includes a ring protection scheme and a span protection scheme.

Claim 5

An optical line switching system according to claim 1 , wherein each of the two unit optical switches has two input ports and two output ports.

Claim 6

An optical line switching system according to claim 1 , wherein the unit optical switches are interlocking switches.

Claim 7

An optical line switching system according to claim 1 , wherein the optical signals are wave division multiplexed signals.

Claim 10

A method according to claim 7 , wherein each of the two unit optical switches has two input ports and two output ports, the common driving mechanism being coupled to the two unit optical switches.

Claim 11

A method according to claim 7 , wherein the optical protection scheme includes a ring protection scheme and a span protection scheme.

Claim 12

A method according to claim 9 , further comprising: amplifying the optical signals; and attenuating the optical signals in response to effecting the ring protection scheme or the span protection scheme.

Claim 13

A method according to claim 7 , wherein the optical signals are wave division multiplexed signals.

Claim 14

An optical communications network providing fault recovery capabilities, comprising: a plurality of optical fibers including working and protection optical fibers; a plurality of nodes exchanging optical signals over the optical fibers, the plurality of nodes being arranged according to a prescribed topology, each of the nodes comprises: (1) an optical switch connected to the optical fibers and configured to switch over the optical signals among the optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; (2) a plurality of monitoring devices coupled to the optical fibers and configured to monitor the optical signals transmitted over the optical fibers and to output selectively monitoring signals that indicate one or more faults in the optical fibers; and (3) a control device coupled to the monitoring devices and configured to output a control signal to the optical switches to effect an optical protection scheme by selectively changing switching states of the optical switch in response to the monitoring signals, wherein the working and protection optical fibers are respectively independently paired such that only two unit optical switches are required for each pair of the working and protection optical fibers to independently implement the optical protection scheme.

Claim 15

An optical communications network providing fault recovery capabilities, comprising: a plurality of optical fibers including working and protection optical fibers; a plurality of nodes exchanging optical signals over the optical fibers, the plurality of nodes being arranged according to a prescribed topology, each of the nodes comprises: (1) an optical switch connected to the optical fibers and configured to switch over the optical signals among the optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; (2) a plurality of monitoring devices coupled to the optical fibers and configured to monitor the optical signals transmitted over the optical fibers and to output selectively monitoring signals that indicate one or more faults in the optical fibers; and (3) a control device coupled to the monitoring devices and configured to output a control signal to the optical switches to effect an optical protection scheme by selectively changing switching states of the optical switch in response to the monitoring signals, wherein the working and protection optical fibers are respectively independently paired such that only two unit optical switches are required for each pair of the working and protection optical fibers to independently implement the optical protection scheme.

Claim 16

An optical communications network according to claim 12 , wherein at least one of the nodes further comprises an optical signal processing device coupled to the optical switch and configured to perform adding/dropping and multiplexing/demultiplexing of the optical signals.

Claim 17

An optical communications network according to claim 12 , wherein the topology is in form of a ring, the optical signals being wave division multiplexed signals.

Claim 18

An optical communications network according to claim 12 , wherein each of the two unit optical switches has two input ports and two output ports.

Claim 19

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the optical switch is a 4×4 matrix optical switch that comprises two independent optical switches, each of the two independent switches including two of the unit optical switches.

Claim 20

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the optical switch is a 4×4 matrix optical switch that comprises two independent optical switches, each of the two independent switches including two of the unit optical switches.

Claim 21

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals; and an optical signal processing device coupled to the optical switch and configured to perform adding/dropping and multiplexing/demultiplexing of the optical signals, wherein the optical switch constituting a first optical switch, the optical line switching system further comprising: a second optical switch coupled between the optical signal processing device and the first optical switch; and a third optical switch coupled between the optical signal processing device and the first optical switch.

Claim 22

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals; and an optical signal processing device coupled to the optical switch and configured to perform adding/dropping and multiplexing/demultiplexing of the optical signals, wherein the optical switch constituting a first optical switch, the optical line switching system further comprising: a second optical switch coupled between the optical signal processing device and the first optical switch; and a third optical switch coupled between the optical signal processing device and the first optical switch.

Claim 23

An optical line switching system according to claim 17 , further comprising a fourth optical switch coupled to the second optical switch and the third optical switch, wherein the second optical switch and the third optical switch are situated between the fourth optical switch and the first optical switch.

Claim 24

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the optical switch comprises two unit optical switches, each of the unit optical switches having two input ports and two output ports.

Claim 25

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the optical switch comprises two unit optical switches, each of the unit optical switches having two input ports and two output ports.

Claim 26

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the unit optical switches are interlocking switches.

Claim 27

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the unit optical switches are interlocking switches.

Claim 28

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the optical switch constituting a first optical switch, the optical line switching system further comprising: an optical signal processing device configured to perform adding/dropping and multiplexing/demultiplexing of the optical signals; a second optical switch configured to change switching state upon receiving the control signal from the control device; a first optical amplifier situated between the first optical switch and the second optical switch and configured to amplify the optical signals; a second optical amplifier configured to amplify the optical signals; and a third optical amplifier configured to amplify the optical signals, wherein the optical signal processing device is coupled between the first optical switch and the second optical switch, and wherein the optical signal processing device is coupled between the second optical amplifier and the third optical amplifier.

Claim 29

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring signals, wherein the optical switch constituting a first optical switch, the optical line switching system further comprising: an optical signal processing device configured to perform adding/dropping and multiplexing/demultiplexing of the optical signals; a second optical switch configured to change switching state upon receiving the control signal from the control device; a first optical amplifier situated between the first optical switch and the second optical switch and configured to amplify the optical signals; a second optical amplifier configured to amplify the optical signals; and a third optical amplifier configured to amplify the optical signals, wherein the optical signal processing device is coupled between the first optical switch and the second optical switch, and wherein the optical signal processing device is coupled between the second optical amplifier and the third optical amplifier.

Claim 30

An optical line switching system according to claim 21 , further comprising an optical attenuator configured to attenuate selectively the optical signals upon effecting of the optical protection scheme, the optical attenuator being situated upstream from the first optical amplifier.

Claim 31

An optical line switching system according to claim 21 , further comprising a third optical switch configured to change switching state upon receiving the control signal from the control device and being coupled between the first optical switch and the second optical switch.

Claim 32

An optical line switching system according to claim 21 , further comprising: a first optical attenuator coupled between two ports of the first optical switch; and a second optical attenuator coupled between two ports of the second optical switch, wherein the first optical attenuator and the second optical attenuator are configured to attenuate selectively the optical signals.

Claim 33

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring devices, wherein the unit optical switches possess three connection states.

Claim 34

An optical line switching system comprising: an optical switch connected to working optical fibers and protection optical fibers, the optical switch being configured to switch over optical signals among the working optical fibers and the protection optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; a plurality of monitoring devices coupled to the working optical fibers and the protection optical fibers and configured to monitor the optical signals transmitted over the working optical fibers and the protection optical fibers and to output selectively monitoring signals that indicate one or more faults in the working optical fibers and the protection optical fibers; and a control device coupled to the monitoring devices and configured to output a control signal to the unit optical switches to effect an optical protection scheme by selectively changing switching states of the unit optical switches in response to the monitoring devices, wherein the unit optical switches possess three connection states.

Claim 39

An optical communications network providing fault recovery capabilities, comprising: a plurality of optical fibers; a plurality of nodes exchanging optical signals over the optical fibers, the plurality of nodes being arranged according to a prescribed topology, each of the nodes comprises: (1) an optical switch connected to the optical fibers and configured to switch over the optical signals among the optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; (2) a plurality of monitoring devices coupled to the optical fibers and configured to monitor the optical signals transmitted over the optical fibers and to output selectively monitoring signals that indicate one or more faults in the optical fibers; and (3) a control device coupled to the monitoring devices and configured to output a control signal to the optical switches to effect an optical protection scheme by selectively changing switching states of the optical switch in response to the monitoring signals, wherein the optical switch is a 4×4 optical switch comprising two dual 2×2 optical switches that are interlocking type optical switches.

Claim 40

An optical communications network providing fault recovery capabilities, comprising: a plurality of optical fibers; a plurality of nodes exchanging optical signals over the optical fibers, the plurality of nodes being arranged according to a prescribed topology, each of the nodes comprises: (1) an optical switch connected to the optical fibers and configured to switch over the optical signals among the optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; (2) a plurality of monitoring devices coupled to the optical fibers and configured to monitor the optical signals transmitted over the optical fibers and to output selectively monitoring signals that indicate one or more faults in the optical fibers; and (3) a control device coupled to the monitoring devices and configured to output a control signal to the optical switches to effect an optical protection scheme by selectively changing switching states of the optical switch in response to the monitoring signals, wherein the optical switch is a 4×4 optical switch comprising two dual 2×2 optical switches that are interlocking type optical switches.

Claim 41

An optical communications network providing fault recovery capabilities, comprising: a plurality of optical fibers; a plurality of nodes exchanging optical signals over the optical fibers, the plurality of nodes being arranged according to a prescribed topology, each of the nodes comprises: (1) an optical switch connected to the optical fibers and configured to switch over the optical signals among the optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; (2) a plurality of monitoring devices coupled to the optical fibers and configured to monitor the optical signals transmitted over the optical fibers and to output selectively monitoring signals. that indicate one or more faults in the optical fibers; and (3) a control device coupled to the monitoring devices and configured to output a control signal to the optical switches to effect an optical protection scheme by selectively changing switching states of the optical switch in response to the monitoring signals, wherein the optical switch comprises two unit optical switches, each of the unit optical switches having two input ports and two output ports.

Claim 42

An optical communications network providing fault recovery capabilities, comprising: a plurality of optical fibers; a plurality of nodes exchanging optical signals over the optical fibers, the plurality of nodes being arranged according to a prescribed topology, each of the nodes comprises: (1) an optical switch connected to the optical fibers and configured to switch over the optical signals among the optical fibers, wherein the optical switch comprises a plurality of unit optical switches and a common driving mechanism configured to perform simultaneously switching operation of the unit optical switches to alter a switching state of the optical switch; (2) a plurality of monitoring devices coupled to the optical fibers and configured to monitor the optical signals transmitted over the optical fibers and to output selectively monitoring signals. that indicate one or more faults in the optical fibers; and (3) a control device coupled to the monitoring devices and configured to output a control signal to the optical switches to effect an optical protection scheme by selectively changing switching states of the optical switch in response to the monitoring signals, wherein the optical switch comprises two unit optical switches, each of the unit optical switches having two input ports and two output ports.