Abstract: 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.

Abstract: An example system includes a plurality of hub transceivers and a plurality of edge transceivers. A first hub transceiver is operable to determine that the first hub transceiver is configured to assign a first subset of network resources to a first subset of the edge transceivers for communication over an optical communications network, and determine that a second hub transceiver is configured to assign a second subset of network resources to a second subset of the edge transceivers for communication over the optical communications network. The first hub transceiver is also operable to determine that the first subset of network resources overlaps the second subset of network resources, and in response, transmit a notification of the overlap to a control module of the optical communications network.

Abstract: Techniques are described for implementing an out-of-band communication channel used to exchange control channel information in sub-carrier-based optical communication systems. In an example implementation, an apparatus includes laser operable to supply an optical signal, a digital signal processor operable to supply digital signals, a digital to analog circuitry operable to provide analog signals based on the digital signals, and driver circuitry is coupled to the digital to analog circuitry and operable to supply at least one drive signal. The apparatus also includes a modulator operable to receive said at least one drive signal, modulate the optical signal based on said at least one drive signal to provide a plurality of optical subcarriers, amplitude modulate the plurality of optical subcarriers at a first frequency to carry first control information, and modulate the plurality of subcarriers at a second frequency to carry second control information.

Abstract: Techniques are described for implementing an out-of-band communication channel used to exchange control channel information in sub-carrier-based optical communication systems. In an example implementation, an apparatus includes an optical tap coupled to an optical communication path carrying a modulated optical signal carrying a plurality of optical subcarriers. The optical tap has a first output configured to supply a first portion of the modulated optical signal and a second output configured to supply a second portion of the modulated optical signal. The plurality of optical subcarriers are amplitude modulated based on control data at a first frequency, and each of the plurality of optical subcarriers is modulated to carry user data at a second frequency greater than the first frequency. The apparatus is configured to supply the control based on the first portion of the modulated optical signal.

Abstract: Techniques are described for implementing an out-of-band communication channel used to exchange control channel information in sub-carrier-based optical communication systems. In an example implementation, an optical communication system includes a primary transceiver, a component, and secondary transceivers. The primary transceiver is operable to supply first optical subcarriers to an optical communication path, the first optical subcarriers being amplitude modulated at a first frequency to carry first control information and amplitude modulated at a second frequency to carry second control information. The component is operable to be coupled to the optical communication path and includes circuitry operable to detect the first control information. The secondary transceivers are coupled to a terminal end of the optical communication path. At least one of the secondary transceivers is operable to detect the second control information and block the first control information.

Abstract: Techniques are described for implementing an out-of-band communication channel used to exchange control channel information in sub-carrier-based optical communication systems. In an example implementation, a transmitter includes a laser operable to supply an optical signal, a digital signal processor operable to supply first electrical signals based on first data input to the digital signal processor and second data input to the digital signal processor, digital-to-analog conversion circuitry operable to output second electrical signals based on the first electrical signals, modulator driver circuitry is operable to output third electrical signals based on the second electrical signals, and an optical modulator operable to supply first and second modulated optical signals based on the third electrical signals. The first modulated optical signal includes a plurality of optical subcarriers carrying user data. The second modulated optical signal is polarization modulated based on the second data.

Abstract: Methods, systems, and apparatus for subcarrier modulation with radio frequency inphase-quadrature (IQ) modulators. A system includes a plurality of IQ modulators, each configured to receive an input electrical signal comprising an inphase signal and a quadrature signal, and each configured to modulate the inphase signal and quadrature signal based on one of a plurality of local oscillator signals to output a multiplexed signal. Each of the plurality of local oscillator signals is supplied by a respective one of a plurality of local oscillator circuits. A modulator circuit is configured to modulate a carrier optical signal from a laser having a frequency ?c based on the multiplexed signal to generate a modulated optical signal centered at frequency ?c and comprising a plurality of subcarriers. A center frequency of each of the plurality of subcarriers is offset from ?c by a frequency of said one of the plurality of local oscillator signals.

Abstract: A device may be configured to receive a text file including network information for an optical network. The network information may include information for an optical route in the optical network. The device may generate a user interface based on the text file. The user interface may display a representation of the optical route. The device may provide the user interface for display and receive a user input via the user interface. The device may change the representation of the optical route displayed by the user interface based on the user input and the network information included in the text file.

Abstract: A method of distributing a plurality of data files to a plurality of recipients including the steps of: placing encrypted copies of the data files to be distributed on a plurality of identical media and providing the recipients with media reading devices having data file decryption capability; logically arranging the data files into data file groups; in response to a recipient's request for access to selected file groups providing the recipient with a group access map indicative of the file groups to which access is requested; in further response to a recipient's request for access to selected file groups providing the recipient with a password to be used for access verification; completing an access verification operation using the group access map and the password and data indicative of the media being read and data indicative of the reading device being used; providing access to the data files in the file groups to which access is requested by use of the group access map; and decrypting the accessed data f