Abstract: In accordance with embodiments of the present disclosure, a method for demand aggregation is provided. The method may include routing demands in a ring network such that a length for each routed demand does not exceed a route length maximum, and a load imbalance at each node in the ring network is minimized. The method may also include maximizing optical line card sharing by assigning routed demands sharing common ends to the same wavelength.

Abstract: A system is provided for electrical domain optical spectrum shaping. The system may include a laser, a modulator, a first electrical filter, and a second electrical filter. The laser may be configured to output an optical carrier signal. The modulator may be configured to modulate the optical carrier signal to output a modulated optical signal based on a first filtered input signal and a second filtered input signal received by the modulator. The first electrical filter may be configured to filter a first input signal to produce the first filtered input signal. The second electrical filter may be configured to filter a second input signal to produce the second filtered input signal.

Abstract: In certain embodiments, minimizing interconnections in a multi-shelf switching system includes receiving a map describing the switching system, where the switching system comprises shelves and input/output (I/O) points. The map is transformed to yield a graph comprising nodes and edges. A node represents an I/O point, and a node weight represents a number of interface cards of the I/O point represented by the node. An edge between a node pair represents traffic demand between the I/O points represented by the node pair, and an edge weight represents the amount of the traffic demand represented by the edge. The graph is partitioned to yield a groups that minimize interconnection traffic among the shelves, where each group represents a shelf of the multi-shelf switching system.

Abstract: According to particular embodiments, reducing cross-phase modulation includes sending instructions to a phase modulation array comprising channel pixel sets that modulate phases of channels. The channel pixel sets comprise a first channel pixel set that modulates a first phase of a first channel and a second channel pixel set that modulates a second phase of a second channel that uses a phase modulation format. The first channel pixel set is instructed to modulate the first phase at a first constant phase. The second channel pixel set is instructed to modulate the second phase at a second constant phase different from the first constant phase in order to create a group delay between the first channel and the second channel.

Abstract: Methods and systems are provided for compensating impairment of a signal in an optical network. A method may include: (i) recording, for each node of a plurality nodes of the network, traffic management information specific to such node; (ii) communicating, by each node, its associated traffic management information to one or more other nodes; (iii) receiving, at a particular node of the plurality of nodes, the traffic management information communicated from the one or more nodes; (iv) determining, by the particular node, digital signal processor tap coefficients for a digital coherent receiver integral to the particular node based on at least a portion of the traffic management information; and (v) compensating, by the digital coherent receiver, optical impairment of the optical signal based on at least the determined digital signal processor tap coefficients and processing of the optical signal by a digital signal processor integral to the digital coherent receiver.

Abstract: An optical node may include a plurality of optical input components operable to receive a plurality of signals communicated in an optical network and a plurality of optical output components operable to transmit a plurality of signals to be communicated in the optical network.

Abstract: According to particular embodiments, determining paths in a network with asymmetric switches includes receiving a graph representing the network. Each asymmetric switch has defined degree connectivity between one or more pairs of degrees of the asymmetric switch. The graph is transformed to yield a transformed graph that accounts for the asymmetric switches. A routing process is applied to the transformed graph to yield one or more paths through the network.

Abstract: In accordance with the teachings of the present invention, a system and method for managing communication in a hybrid passive optical network (HPON) is provided. In a particular embodiment, the method includes transmitting, at a first wavelength, a first configuration message on the HPON. The method also includes receiving at one or more of a plurality of receivers at an optical line terminal (OLT) one or more configuration response messages from one or more optical network units (ONUs) in a first set of ONUs. The method further includes, based on the configuration response messages from the first set of ONUs, associating, in a database, each ONU in the first set of ONUs with the first wavelength and with the receiver receiving the configuration response message from the ONU. The method also includes, after transmitting the first configuration message, transmitting, at a second wavelength, a second configuration message on the HPON.

Abstract: According to particular embodiments, determining disjoint paths includes receiving a graph representing a network comprising nodes and links. The graph is transformed such that the number of intermediate nodes of a path indicates the number of regenerators for the path. A set of seed paths from a source node to a destination node of the transformed graph is generated. For each seed path, a shortest path from the source node to the destination node is determined to yield one or more pairs of disjoint paths from the source node to the destination node. An optimized pair of disjoint paths is selected, where the optimized pair of disjoint paths has an optimized number of regenerators.

Abstract: According to one embodiment, allocating demand includes receiving a demand graph that describes demands of a network. One or more weights are calculated for each demand. The demands are allocated according to the weights of the demands to optimize optical line card sharing.

Abstract: Providing protection for a network includes establishing a light-trail through a sequence of nodes of an optical network, where the sequence of nodes is coupled by a first fiber and by a second fiber. Traffic is communicated through a plurality of connections of the light-trail, where a connection is operable to communicate traffic from a source node of the sequence of nodes to one or more destination nodes of the sequence of nodes. A failure of the light-trail is detected. A protection light-trail corresponding to the light-trail is established. The traffic of the plurality of connections is communicated through the protection light-trail.

Abstract: An optical network is provided that carries optical traffic in multiplexed wavelengths between a number of nodes. The network includes at least one light-trail associated with one of the wavelengths and established between a subset of the nodes in the network. The network also includes an out-of-band control channel that is associated with a different wavelength than the light-trail. The control channel is used to communicate control messages to establish the light-trail and to allocate use of the light-trail by the subset of nodes. Each of the subset of nodes comprises a burstponder operable to receive data traffic from one or more client devices of the associated node to be communicated over the light-trail and to buffer the received data traffic and assemble the data traffic into an optical payload.

Abstract: A method includes transmitting, at a first wavelength, a first configuration message on the PON including a first transmitter interface number and transmitting, at a second wavelength, a second configuration message on the PON including a second transmitter interface number. The method further includes receiving a configuration response message from a first set of ONUs that comprises the first transmitter interface number and from a second set of ONUs that comprises the second transmitter interface, associating the first set of ONUs with the first wavelength and the second set of ONUs with the second wavelength, and transmitting downstream traffic destined for any ONU in the first set of ONUs at the first wavelength and transmitting downstream traffic for any ONU in the second set of ONUs at the second wavelength.

Abstract: An optical network is disclosed that carries optical traffic in multiplexed wavelengths between a number of nodes. The network includes at least one light-trail associated with one of the wavelengths and established between a convener node and an end node, and including one or more intervening nodes. The network also includes an out-of-band control channel that is associated with a different wavelength than the light-trail. The control channel is used to communicate control messages to establish the light-trail and to allocate use of the light-trail by the convener node and the intervening nodes. Each of the convener node, the one or more intervening nodes, and the end node is operable to receive optical traffic in a number of multiplexed wavelengths from the optical network, drop a first copy of the multiplexed optical traffic from the optical network, and forward a second copy of the multiplexed optical traffic on the optical network.

Abstract: A method for communicating optical traffic includes adding optical traffic to an optical ring comprising a plurality of nodes and communicating the optical traffic on the optical ring. The optical traffic comprises a plurality of virtual wavebands which comprise a first virtual waveband of traffic comprising a first number of wavelengths and a second virtual waveband of traffic comprising a second number of wavelengths. The second number is different from the first number. The method also includes dropping the first virtual waveband of traffic at a first node of the plurality of nodes and dropping the second virtual waveband of traffic at a second node of the plurality of nodes.

Abstract: In accordance with the teachings of the present invention, a system and method for managing communication in a hybrid passive optical network (HPON) is provided. In a particular embodiment, the method includes transmitting, at a first wavelength, a first configuration message on the HPON. The method also includes receiving at one or more of a plurality of receivers at an optical line terminal (OLT) one or more configuration response messages from one or more optical network units (ONUs) in a first set of ONUs. The method further includes, based on the configuration response messages from the first set of ONUs, associating, in a database, each ONU in the first set of ONUs with the first wavelength and with the receiver receiving the configuration response message from the ONU. The method also includes, after transmitting the first configuration message, transmitting, at a second wavelength, a second configuration message on the HPON.

Abstract: A method for protection switching includes receiving an optical signal from a transponder coupled to a client and optically splitting the signal to a first output and a second output. The first output is coupled by a first optical add-drop multiplexer to a first optical fiber, and the second output is coupled by a second add-drop multiplexer to a second fiber. The method further includes selecting one of the output signals for the working channel, and communicating the selected output signal to an optical network. During communication of the selected output signal to the optical network, the method includes monitoring for a failure condition in the optical network and, if the failure condition is detected, selecting the other output signal as the working channel and communicating the new selected output signal.

Abstract: An optical node includes a plurality of optical input components operable to receive a plurality of signals communicated in an optical mesh network. A plurality of optical drop components coupled to the plurality of optical input components, each optical drop component operable to select a signal to drop to one or more associated client devices from any one of the plurality of optical input components. A plurality of optical output components operable to transmit a plurality of signals to be communicated in the optical mesh network, and a plurality of optical add components coupled to the plurality of optical output components and operable to transmit copies of a plurality of optical add signals to the plurality of optical output components. Each optical output component is operable to select a signal to communicate in the optical mesh network received from any one of the plurality of optical add components and the plurality of optical input components.

Abstract: A method for optical supervisory signaling includes determining a wavelength channel status (WCS) value, a wavelength channel failure (WCF) value, and a wavelength channel lit (WCL) value for each one of multiple data channels services by an optical communication node. The method further includes communicating the values to a second optical communication node.

Abstract: In accordance with the teachings of the present invention, a system and method for managing network components in a passive optical network (PON) is provided. In a particular embodiment, the method includes transmitting, at a first wavelength, a first configuration message on the PON, wherein the first configuration message comprises a first transmitter interface number. The method also includes transmitting, at a second wavelength and at approximately the same time as the first message, a second configuration message on the PON, wherein the second configuration message comprises a second transmitter interface number. The method further includes receiving a configuration response message from each of one or more optical network units (ONUs) in a first set of ONUs that comprises the first transmitter interface number and receiving a configuration response message from each of one or more ONUs in a second set of ONUs that comprises the second transmitter interface number.