Abstract: SONET/SDH ring aggregation with distributed traffic. The system may include a packet-switched fabric adapted to switch TDM and PDU over the same fabric. The system provides logical functionality of one or more of SONET/SDH ADMs, fiber patch panels, coax patch panels, DCSs, and packet switches. Integrated management provides management of remote ADMs attached to multiple SONET/SDH rings, even of ADMs manufactured by different vendors. A management system may provide native termination of OSI over DCC and IP over DCC to provide integration of equipment from various vendors.

Abstract: A router identifies in a data packet an address of a network device. An algorithm determines that the address and a first prefix in a tree data structure match up to a first mask length of the first prefix. The algorithm maintains the first prefix in a temporary storage location if there is a match, and determines whether the address and a second prefix in the tree data structure match up to a second mask length of the second prefix, wherein an external node of the second prefix is linked below an external node of the first prefix, and wherein the second mask length is longer than the first mask length. The algorithm maintains the second prefix as a better match of the address, if the address and the second prefix match up to the mask length of the second prefix.

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: To automatically discover the port connections for all nodes in a network, a master node generates a predetermined optical signal and transmits the predetermined optical signal to a neighboring node, which signal identifies the port on which the master node transmitted the predetermined signal. The recipient transmits a reply signal to the predecessor node and to the master node via a control channel, which identifies a port on which the predetermined optical signal was received by the neighboring node. By successively repeating this process in a methodical manner, the master node can discover all of the port interconnections in the optical network. Also each node can discover all its port interconnections to its neighbors. Moreover, by selecting controlling the state (e.g., terminate, open) of the ports of the non-master nodes in the network, the master node can control which nodes receive the predetermined signal, thereby ensuring proper port discovery.

Abstract: The techniques described herein allow a more efficient transmuxing operation for transferring data from a synchronous domain (e.g., SONET) to a plesiochronous (e.g., PDH) domain as compared to the prior art, in which extraction of data streams, jitter filtering and stuff bit generation are processed separately. The techniques described herein include extraction of data from the plesiochronous data stream without complete extraction of the underlying native data stream. Filtering is performed based on synchronous timing, which results in a simpler filter design.

Abstract: A technique for allocating protection-switching mechanisms operates on a per wavelength basis. This allows a designer of an optical network to select a particular protection switching mechanism for a given traffic type, which is usually specific to a particular wavelength in an optical network. For another traffic type, the designer can allocate a different protection switching mechanism, thereby providing optimal protection switching for each traffic type.

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: To automatically discover the port connections for all nodes in a network, a master node generates a predetermined optical signal and transmits the predetermined optical signal to a neighboring node, which signal identifies the port on which the master node transmitted the predetermined signal. The recipient transmits a reply signal to the predecessor node and to the master node via a control channel, which identifies a port on which the predetermined optical signal was received by the neighboring node. By successively repeating this process in a methodical manner, the master node can discover all of the port interconnections in the optical network. Also each node can discover all its port interconnections to its neighbors. Moreover, by selecting controlling the state (e.g., terminate, open) of the ports of the non-master nodes in the network, the master node can control which nodes receive the predetermined signal, thereby ensuring proper port discovery.

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 reconfigurable optical switch having a plurality of input ports and at least one output port. The node also includes a plurality of transmitters that are each coupled to one of the input ports of the optical switch. Each of the transmitters generate an information-bearing optical signal at a different channel wavelength from one another. The reconfigurable optical switch is adaptable to receive at any of the input ports any of the channel wavelengths at which the plurality of transmitters operate and direct the channel wavelengths to the output port. At least one backup transmitter is coupled to one of the input ports of the optical switch. The backup transmitter includes a tunable laser tunable to any of the channel wavelengths at which the plurality of transmitters operate.

Abstract: An optical switch is provided which includes a plurality of input/output ports for receiving one or more wavelength component(s) of an optical signal. The optical switch also includes an optical arrangement that directs the wavelength component to any given one of the plurality of input/output ports. The given input/output port may be selected from among any of the plurality of input/output ports. If the optical signal includes a plurality of wavelength components, the optical arrangement includes at least one wavelength selective element such as a thin film filter. The wavelength selective element selects one of the wavelength components from among the plurality of wavelength components. The optical arrangement also includes a plurality of optical elements each associated with one of the wavelength selective elements.

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: In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided that includes a reconfigurable optical switch having a plurality of input ports and at least one output port. The node also includes a plurality of transmitters that are each coupled to one of the input ports of the optical switch. Each of the transmitters generate an information-bearing optical signal at a different channel wavelength from one another. The reconfigurable optical switch is adaptable to receive at any of the input ports any of the channel wavelengths at which the plurality of transmitters operate and direct the channel wavelengths to the output port. At least one backup transmitter is coupled to one of the input ports of the optical switch. The backup transmitter includes a tunable laser tunable to any of the channel wavelengths at which the plurality of transmitters operate.

Abstract: An optical switch is provided which includes a plurality of input/output ports for receiving one or more wavelength component(s) of an optical signal. The optical switch also includes an optical arrangement that directs the wavelength component to any given one of the plurality of input/output ports. The given input/output port may be selected from among any of the plurality of input/output ports. If the optical signal includes a plurality of wavelength components, the optical arrangement includes at least one wavelength selective element such as a thin film filter. The wavelength selective element selects one of the wavelength components from among the plurality of wavelength components. The optical arrangement also includes a plurality of optical elements each associated with one of the wavelength selective elements.

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: A method for merging protection switching messages in an optical network enables a control of the amount of message bandwidth used for sending protection switching messages. A method for performing protection switching in an optical network does so in an optimal manner by performing the protection switching actions in the various nodes of a protection path in parallel rather than in sequence. To do so, a channel failure message is transmitted from an end node A in the optical network upon detecting a failure in a link in the optical network that includes the end node A. If a failure can be detected at both end nodes, the channel failure messages are transmitted from both end nodes the moment they detect failure without any further waiting. Upon receiving the first channel failure message regardless its originating end node, switching actions in intermediate nodes are initiated.

Abstract: A method for performing protection switching in an optical network does so in an optimal manner by performing the protection switching actions in the various nodes of a protection path in parallel rather than in sequence. To do so, a channel failure message is transmitted from an end node A in the optical network upon detecting a failure in a link in the optical network that includes the end node A. If a failure can be detected at both end nodes, the channel failure messages are transmitted from both end nodes the moment they detect failure without any further waiting. Upon receiving the first channel failure message regardless its originating end node, switching actions in intermediate nodes are initiated. The channel failure messages are forwarded from the intermediate nodes to their corresponding next nodes before completing switching actions in the intermediate nodes.