Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided which includes an optical coupling arrangement having at least one input port for receiving a WDM signal and a plurality of output ports for selectively receiving one or more wavelength components of the WDM optical signal. The optical coupling arrangement is adaptable to reconfigure its operational state to (i) selectively direct any one of the wavelength components received on the input port to any of the output ports independently of any other of the wavelength components and (ii) selectively direct any combination of two or more of the wavelength components from the input port to at least two of the output ports that serve as WDM output ports. At least one optical WDM interface is optically coupled to a first of the WDM output ports.

Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided which includes an optical coupling arrangement having at least one input port for receiving a WDM signal and a plurality of output ports for selectively receiving one or more wavelength components of the WDM optical signal. The optical coupling arrangement is adaptable to reconfigure its operational state to (i) selectively direct any one of the wavelength components received on the input port to any of the output ports independently of any other of the wavelength components and (ii) selectively direct any combination of two or more of the wavelength components from the input port to at least two of the output ports that serve as WDM output ports. At least one optical WDM interface is optically coupled to a first of the WDM output ports.

Abstract: A method and apparatus is provided for reducing impairment to an adiabatically chirped optical signal propagating in an optical communication system. The method begins by receiving an adiabatically chirped optical signal that has traversed one or more network components in the optical communication system. The optical signal has a parameter characteristic of signal quality (e.g., an extinction ratio) that is reduced at least in part by a fidelity-degrading transmission slope accumulated in the one or more network components. A fidelity-enhancing transmission slope imparted to at least one wavelength of the adiabatically chirped optical signal at one or more select points along a transmission path of the communication system so that the optical signal experiences an increase in said parameter characteristic of signal quality.

Abstract: An all-optical, optical cross-connect includes first and second pluralities of multiport optical devices. Each of the first plurality of multiport optical devices have at least one input port for receiving a WDM optical signal and a plurality of output ports for selectively receiving one of more wavelength components of the optical signal. Each of the second plurality of multiport optical devices have a plurality of input ports for selectively receiving one of more wavelength components of the optical signal and at least one output port for selectively receiving one of more wavelength components of the optical signal. At least one of the first or second plurality of multiport optical devices are all-optical switches that can route every wavelength component independently of every other wavelength component.

Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided that includes a first plurality of transponders each generating and/or receiving an information-bearing optical signal at a different channel wavelength from one another. An optical coupling arrangement, which may include one or more reconfigurable optical switches, transfers the channel wavelengths between a link connected to the node and the first plurality of transponders. The arrangement is adaptable to reconfigure its operational state to selectively direct different ones of the channel wavelengths from the link to different ones of the transponders without disturbing the optical path through the node traversed by any other channel wavelengths. A communications and configuration arrangement is provided, which transfers data identifying the respective channel wavelengths at which the transponders operate from the transponders to the optical coupling arrangement.

Abstract: An optical switch includes at least one input port for receiving a plurality of channel wavelengths of an optical signal and a plurality of output ports. A plurality of wavelength selective elements are also provided, which each select a channel wavelength from among the plurality of channel wavelengths received at the input port. A plurality of optical elements are respectively associated with the plurality of wavelength selective elements. Each of the optical elements direct one of the selected channel wavelengths, which are selected by the associated wavelength selective element, to any one of the output ports independently of all other channel wavelengths and with a selectively variable degree of attenuation. The switch also includes a controller for adjusting a configuration of the optical elements to provide the channel wavelengths with the selectively variable degree of attenuation.

Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided that includes a first plurality of transponders each generating and/or receiving an information-bearing optical signal at a different channel wavelength from one another. An optical coupling arrangement, which may include one or more reconfigurable optical switches, transfers the channel wavelengths between a link connected to the node and the first plurality of transponders. The arrangement is adaptable to reconfigure its operational state to selectively direct different ones of the channel wavelengths from the link to different ones of the transponders without disturbing the optical path through the node traversed by any other channel wavelengths. A communications and configuration arrangement is provided, which transfers data identifying the respective channel wavelengths at which the transponders operate from the transponders to the optical coupling arrangement.

Abstract: An all-optical, optical cross-connect includes first and second pluralities of multiport optical devices. Each of the first plurality of multiport optical devices have at least one input port for receiving a WDM optical signal and a plurality of output ports for selectively receiving one of more wavelength components of the optical signal. Each of the second plurality of multiport optical devices have a plurality of input ports for selectively receiving one of more wavelength components of the optical signal and at least one output port for selectively receiving one of more wavelength components of the optical signal. At least one of the first or second plurality of multiport optical devices are all-optical switches that can route every wavelength component independently of every other wavelength component.

Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided which includes an optical coupling arrangement having at least one input port for receiving a WDM signal and a plurality of output ports for selectively receiving one or more wavelength components of the WDM optical signal. The optical coupling arrangement is adaptable to reconfigure its operational state to (i) selectively direct any one of the wavelength components received on the input port to any of the output ports independently of any other of the wavelength components and (ii) selectively direct any combination of two or more of the wavelength components from the input port to at least two of the output ports that serve as WDM output ports. At least one optical WDM interface is optically coupled to a first of the WDM output ports.

Abstract: An all-optical, optical cross-connect includes first and second pluralities of multiport optical devices. Each of the first plurality of multiport optical devices have at least one input port for receiving a WDM optical signal and a plurality of output ports for selectively receiving one of more wavelength components of the optical signal. Each of the second plurality of multiport optical devices have a plurality of input ports for selectively receiving one of more wavelength components of the optical signal and at least one output port for selectively receiving one of more wavelength components of the optical signal. At least one of the first or second plurality of multiport optical devices are all-optical switches that can route every wavelength component independently of every other wavelength component.

Abstract: An all-optical, optical cross-connect includes first and second pluralities of multiport optical devices. Each of the first plurality of multiport optical devices have at least one input port for receiving a WDM optical signal and a plurality of output ports for selectively receiving one of more wavelength components of the optical signal. Each of the second plurality of multiport optical devices have a plurality of input ports for selectively receiving one of more wavelength components of the optical signal and at least one output port for selectively receiving one of more wavelength components of the optical signal. At least one of the first or second plurality of multiport optical devices are all-optical switches that can route every wavelength component independently of every other wavelength component.

Abstract: A WDM optical transmission system is provided that operates at a plurality of channel wavelengths. The system includes at least three nodes at which any one or more of the channel wavelengths can be added or dropped. At least three optical transmission links interconnect the nodes. Each link includes a single waveguide over which travel oppositely-directed WDM signals having channel wavelengths that are interleaved with one another in a pairwise manner. A majority of the optical transmission links each have an optical span loss that corresponds to a level of coherent crosstalk between a reflected channel at a given wavelength co-propagating with a channel at the given wavelength prior to isolating one of the adjacent channels in a node that is less than a level of coherent crosstalk that would otherwise arise if a unidirectional transmission format were employed over a single waveguide in the same system.

Abstract: A method is provided for alleviating congestion in a computer network. The network includes a plurality of nodes interconnected by communication links, which communicate in accordance with at least an optical layer protocol and a second protocol layer. The method begins by receiving a signal in accordance with the optical layer protocol and determining if local forwarding capacity is available to forward the signal in accordance with the second protocol layer. If the local forwarding capacity is unavailable, the method continues by forwarding the signal in accordance with the optical layer protocol to another node having excess capacity so that the other node can forward the signal in accordance with the second protocol layer.

Abstract: A transmission fiber for use in a Raman amplified optical communication system is formed to exhibit certain characteristics that limit modulation instability and four-wave mixing in the amplification region, thus reducing the noise component present in the transmission system. In particular, the group-velocity dispersion (denoted as D and measured in terms of ps/nm-km) is restricted to be either non-positive or greater than +1.5 ps/nm-km in the pump wavelength range of interest (a typical pump wavelength range being 1430-1465 nm). Preferably, the magnitude of the dispersion is kept below a value of 10 ps/nm-km in the signal wavelength range of interest (e.g., the “C” band or “L” band). Four-wave mixing is reduced by ensuring that the zero-dispersion frequency of the transmission fiber is not centered between the pump frequency and a frequency experiencing Raman gain.

Abstract: An all-optical, optical cross-connect includes first and second pluralities of multiport optical devices. Each of the first plurality of multiport optical devices have at least one input port for receiving a WDM optical signal and a plurality of output ports for selectively receiving one of more wavelength components of the optical signal. Each of the second plurality of multiport optical devices have a plurality of input ports for selectively receiving one of more wavelength components of the optical signal and at least one output port for selectively receiving one of more wavelength components of the optical signal. At least one of the first or second plurality of multiport optical devices are all-optical switches that can route every wavelength component independently of every other wavelength component.

Abstract: A method is provided for alleviating congestion in a computer network. The network includes a plurality of nodes interconnected by communication links, which communicate in accordance with at least an optical layer protocol and a second protocol layer. The method begins by receiving a signal in accordance with the optical layer protocol and determining if local forwarding capacity is available to forward the signal in accordance with the second protocol layer. If the local forwarding capacity is unavailable, the method continues by forwarding the signal in accordance with the optical layer protocol to another node having excess capacity so that the other node can forward the signal in accordance with the second protocol layer.

Abstract: An optical switch includes at least one input port for receiving a plurality of channel wavelengths of an optical signal and a plurality of output ports. A plurality of wavelength selective elements are also provided, which each select a channel wavelength from among the plurality of channel wavelengths received at the input port. A plurality of optical elements are respectively associated with the plurality of wavelength selective elements. Each of the optical elements direct one of the selected channel wavelengths, which are selected by the associated wavelength selective element, to any one of the output ports independently of all other channel wavelengths and with a selectively variable degree of attenuation. The switch also includes a controller for adjusting a configuration of the optical elements to provide the channel wavelengths with the selectively variable degree of attenuation.

Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided which includes an optical coupling arrangement having at least one input port for receiving a WDM signal and a plurality of output ports for selectively receiving one or more wavelength components of the WDM optical signal. The optical coupling arrangement is adaptable to reconfigure its operational state to (i) selectively direct any one of the wavelength components received on the input port to any of the output ports independently of any other of the wavelength components and (ii) selectively direct any combination of two or more of the wavelength components from the input port to at least two of the output ports that serve as WDM output ports. At least one optical WDM interface is optically coupled to a first of the WDM output ports.

Abstract: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided that includes a first plurality of transponders each generating and/or receiving an information-bearing optical signal at a different channel wavelength from one another. An optical coupling arrangement, which may include one or more reconfigurable optical switches, transfers the channel wavelengths between a link connected to the node and the first plurality of transponders. The arrangement is adaptable to reconfigure its operational state to selectively direct different ones of the channel wavelengths from the link to different ones of the transponders without disturbing the optical path through the node traversed by any other channel wavelengths. A communications and configuration arrangement is provided, which transfers data identifying the respective channel wavelengths at which the transponders operate from the transponders to the optical coupling arrangement.

Abstract: An all-optical, optical cross-connect includes first and second pluralities of multiport optical devices. Each of the first plurality of multiport optical devices have at least one input port for receiving a WDM optical signal and a plurality of output ports for selectively receiving one of more wavelength components of the optical signal. Each of the second plurality of multiport optical devices have a plurality of input ports for selectively receiving one of more wavelength components of the optical signal and at least one output port for selectively receiving one of more wavelength components of the optical signal. At least one of the first or second plurality of multiport optical devices are all-optical switches that can route every wavelength component independently of every other wavelength component.