A hub node may or have a capacity greater than that of associated leaf nodes. Accordingly, inexpensive leaf nodes may be deployed to receive data carrying optical signals from, and supply data carrying optical signals to, the hub node. One or more connections may couple each leaf node to the hub node, each connection including one or more segments of optical fibers, optical amplifiers, optical splitters/combiners, and optical add/drop multiplexer. Optical subcarriers may be transmitted over such connections, each carrying a data stream. The subcarriers may be generated by a combination of a laser and a modulator. As the capacity requirements of the leaf nodes change, the number of subcarriers associated with, and thus the amount of data provided to, each node, may be changed accordingly.

A first network element includes trail trace identifier information in an optical network frame. The first network element obtains data to transmit over an optical network link to a second network element. The first network element generates an optical network frame with alignment marker bytes, which are followed by padding bytes. The optical network frame also includes overhead bytes following the padding bytes. The overhead bytes include a Multi-Frame Alignment Signal (MFAS) byte, a link status byte, and reserved bytes. The optical network frame also includes a payload bytes following the overhead bytes. The payload bytes encode at least a portion of the data to transmit to the second network element. The first network element inserts trail trace identifier information into the reserved bytes in the overhead bytes. The trail trace identifier information identifies the first network element as a source of the optical network frame.

Consistent the present disclosure, a network or system is provided in which a hub or primary node may communication with a plurality of leaf or secondary nodes. The hub node may operate or have a capacity that may be greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed that receive data carrying optical signals from and supply data carrying optical signals to the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include one or more spans or segments of optical fibers, optical amplifiers, and optical add/drop multiplexer, for example. Consistent with an aspect of the present disclosure, optical subcarriers may be transmitted over such connections. The subcarriers may be generated by a combination of a laser and a modulator, such that multiple lasers and modulators are not required, and costs may be reduced. In addition, the subcarriers may be employed using multiple access techniques, such as frequency division multiplexing (FDM), code-division multiple access (CDMA), and time-division multiple access so that the primary node can communicate with a relatively large number of secondary nodes. In addition, an out-of-band control channel may be provided to carry OAM information from the primary node to the secondary nodes, as well as from the secondary nodes to the primary nodes.

A network or system in which a hub or primary node may communicate with a plurality of leaf or secondary nodes. The hub node may operate or have a capacity greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed to receive data carrying optical signals from, and supply data carrying optical signals to, the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include one or more spans or segments of optical fibers, optical amplifiers, optical splitters/combiners, and optical add/drop multiplexer, for example. Optical subcarriers may be transmitted over such connections, each carrying a data stream. The subcarriers may be generated by a combination of a laser and a modulator, such that multiple lasers and modulators are not required, and costs may be reduced. As the bandwidth or capacity requirements of the leaf nodes change, the number of subcarriers, and thus the amount of data provided to each node, may be changed accordingly. Each subcarrier within a dedicated group of subcarriers may carry OAM or control channel information to a corresponding leaf node, and such information may be used by the leaf node to configure the leaf node to have a desired bandwidth or capacity.

A network or system in which a hub or primary node may communicate with a plurality of leaf or secondary nodes. The hub node may operate or have a capacity greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed to receive data carrying optical signals from, and supply data carrying optical signals to, the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include one or more spans or segments of optical fibers, optical amplifiers, optical splitters/combiners, and optical add/drop multiplexer, for example. Optical subcarriers may be transmitted over such connections, each carrying a data stream. The subcarriers may be generated by a combination of a laser and a modulator, such that multiple lasers and modulators are not required, and costs may be reduced. As the bandwidth or capacity requirements of the leaf nodes change, the number of subcarriers, and thus the amount of data provided to each node, may be changed accordingly. Each subcarrier within a dedicated group of subcarriers may carry OAM or control channel information to a corresponding leaf node, and such information may be used by the leaf node to configure the leaf node to have a desired bandwidth or capacity.

A transmitter can include a laser operable to output an optical signal; a digital signal processor operable to receive user data and provide electrical signals based on the data; and a modulator operable to modulate the optical signal to provide optical subcarriers based on the electrical signals. A first one of the subcarriers carriers carries first TDMA encoded information and second TDMA encoded information, such that the first TDMA encoded information is indicative of a first portion of the data and is carried by the first one of the subcarriers during a first time slot, and the second TDMA encoded information is indicative of a second portion of the data and is carried by the first one of the subcarriers during a second time slot. The first TDMA encoded information is associated with a first node remote from the transmitter and the second TDMA encoded information is associated with a second node remote from the transmitter. A second one of the subcarriers carries third information that is not TDMA encoded, the third information being associated with a third node remote from the transmitter. A receiver and system also are described.

A wavelength multiplexing system is presented comprising at least one basic functional unit extending between input and output light ports. The basic functional unit comprises at least one multi-core fiber. The multi-core fiber comprises N cores configured for supporting transmission of N wavelength channels λ.sub.1, . . . , λ.sub.n, wherein each of said at least one multi-core fibers is configured to apply a predetermined encoding pattern to the wavelength channels enabling linear mixing between them while propagating through multiple cores of said multi-core fiber. The encoding pattern may be configured to affect light propagation paths in the cores by inducing a predetermined dispersion pattern causing linear interaction and mixing between the channels; or may be configured to affect spectral encoding of the channels being transmitted through the cores by applying different weights to the channels.

A wavelength multiplexing system is presented comprising at least one basic functional unit extending between input and output light ports. The basic functional unit comprises at least one multi-core fiber. The multi-core fiber comprises N cores configured for supporting transmission of N wavelength channels λ.sub.1, . . . , λ.sub.n, wherein each of said at least one multi-core fibers is configured to apply a predetermined encoding pattern to the wavelength channels enabling linear mixing between them while propagating through multiple cores of said multi-core fiber. The encoding pattern may be configured to affect light propagation paths in the cores by inducing a predetermined dispersion pattern causing linear interaction and mixing between the channels; or may be configured to affect spectral encoding of the channels being transmitted through the cores by applying different weights to the channels.

A network or system in which a hub or primary node may communicate with a plurality of leaf or secondary nodes. The hub node may operate or have a capacity greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed to receive data carrying optical signals from, and supply data carrying optical signals to, the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include one or more spans or segments of optical fibers, optical amplifiers, optical splitters/combiners, and optical add/drop multiplexer, for example. Optical subcarriers may be transmitted over such connections, each carrying a data stream. The subcarriers may be generated by a combination of a laser and a modulator, such that multiple lasers and modulators are not required, and costs may be reduced. As the bandwidth or capacity requirements of the leaf nodes change, the number of subcarriers, and thus the amount of data provided to each node, may be changed accordingly. Each subcarrier within a dedicated group of subcarriers may carry OAM or control channel information to a corresponding leaf node, and such information may be used by the leaf node to configure the leaf node to have a desired bandwidth or capacity.

A network or system in which a hub or primary node may communicate with a plurality of leaf or secondary nodes. The hub node may operate or have a capacity greater than that of the leaf nodes. Accordingly, relatively inexpensive leaf nodes may be deployed to receive data carrying optical signals from, and supply data carrying optical signals to, the hub node. One or more connections may couple each leaf node to the hub node, whereby each connection may include one or more spans or segments of optical fibers, optical amplifiers, optical splitters/combiners, and optical add/drop multiplexer, for example. Optical subcarriers may be transmitted over such connections, each carrying a data stream. The subcarriers may be generated by a combination of a laser and a modulator, such that multiple lasers and modulators are not required, and costs may be reduced. As the bandwidth or capacity requirements of the leaf nodes change, the number of subcarriers, and thus the amount of data provided to each node, may be changed accordingly. Each subcarrier within a dedicated group of subcarriers may carry OAM or control channel information to a corresponding leaf node, and such information may be used by the leaf node to configure the leaf node to have a desired bandwidth or capacity.