A system and method for obfuscating an optical signal is disclosed. Obfuscating the optical signal may make it more difficult for the optical signal to be detected by an interloper. In one embodiment, an optical signal is received at an optical transmitter, and an obfuscated optical signal is generated by performing a modification of the received optical signal. The obfuscated optical signal is then transmitted from the optical transmitter to an optical receiver. An at least partially deobfuscated optical signal is generated at the optical receiver by performing a modification of the obfuscated optical signal. The modification performed at the optical receiver corresponds to the modification performed at the optical transmitter.

A method for transmission of orbital angular momentum (OAM) data over an optical fiber involves generating an optical signal at a selected wavelength. A ratio of a diameter of a core of the optical fiber to the selected wavelength of the optical signal enables transmission of a predetermined number of orbital angular momentum modes over the optical fiber. The optical signal is modulated with at least one input data stream and an OAM signal is applied to the modulated optical signal to generate the OAM data signal. The OAM data signal is transmitted over the optical fiber using a fiber launcher. A received OAM data signal is processed to extract the at least one input data stream.

Consistent with the present disclosure, an optical switch is provided that switches multiple wavelength division multiplexed (WDM) optical signals. Each of the WDM signals includes optical signals having the same wavelengths. The WDM signals are supplied to optical splitters, which supply power split portions of the WDM signals to corresponding optical gates. Groups of the optical gates are associated with a corresponding switching block, which may include a cyclical arrayed waveguide grating (AWG), and the optical gates within each group are controlled so that one gate passes a received WDM signal portion while the remaining optical gates in the group are in a blocking configuration. As a result, the WDM portion received by the non-blocking gate is demultiplexed in the switching block and each of the wavelength components that constitute the selected WDM portion are supplied to corresponding outputs within the switching block. In a later time interval, a different optical gate may be rendered non-blocking so that a different WDM signal portion, supplied from a different optical splitter and carrying different information over the same wavelengths, may be input to the switching block. Thus, by controlling the optical gates, different WDM signal portions may be switched to, and thus demultiplexed by, a particular switching block. In addition, portions of the same WDM signal may be selectively supplied to different AWGs by appropriately control of the optical gates.

The reception (102) reception unit includes; a first processing unit processing a first signal received from a source channel, and including a filtering unit to filter said first signal in digital domain, and extract unit to extract a information from said first signal; a second processing unit processing a second signal received from a destination channel, and said source channel and said destination channel are distinct each other; a third processing unit providing said information extracted from said first signal to said second signal said third processing unit executes; providing said information from said first processing unit to said second processing unit using information lanes of a clock rate strictly lower than a symbol rate of said second signal, a monitoring unit to generate a monitor signal according to the quality of said second signal; and a control unit controlling a skew between said first signal and said second signal in a bandwidth of said filtering units in said first processing unit.

The reception (102) reception unit includes; a first processing unit processing a first signal received from a source channel, and including a filtering unit to filter said first signal in digital domain, and extract unit to extract a information from said first signal; a second processing unit processing a second signal received from a destination channel, and said source channel and said destination channel are distinct each other; a third processing unit providing said information extracted from said first signal to said second signal said third processing unit executes; providing said information from said first processing unit to said second processing unit using information lanes of a clock rate strictly lower than a symbol rate of said second signal, a monitoring unit to generate a monitor signal according to the quality of said second signal; and a control unit controlling a skew between said first signal and said second signal in a bandwidth of said filtering units in said first processing unit.

A light transmitter to transmit multiple light packets, each formatted to include a same message comprising a series of bits, each bit represented as light that is intensity modulated over a bit period at a frequency indicative of the bit. The light packets are transmitted at different start-times to establish different phases, one for each of the light packets, to permit a light receiver to sample each message at a different phase of a fixed sample timeline that is asynchronous to the bit period and the frequency. The light receiver samples the multiple light packets based on the sample timeline, to sample each received message at one of the different sample phases, then constructs a best series of bits based on the multiple demodulated messages.

A light transmitter to transmit multiple light packets, each formatted to include a same message comprising a series of bits, each bit represented as light that is intensity modulated over a bit period at a frequency indicative of the bit. The light packets are transmitted at different start-times to establish different phases, one for each of the light packets, to permit a light receiver to sample each message at a different phase of a fixed sample timeline that is asynchronous to the bit period and the frequency. The light receiver samples the multiple light packets based on the sample timeline, to sample each received message at one of the different sample phases, then constructs a best series of bits based on the multiple demodulated messages.

Cross-layer information associated with a software defined networking-based (SDN-based) communication network is collected. One or more updates are sent to one or more network elements in the SDN-based communication network to control one or more local decisions made at the one or more network elements. The one or more updates are based on at least a portion of the collected cross-layer information. Preferably, the collecting and sending steps are performed by a controller implementing an SDN management plane associated with the SDN-based communication network.

A procedure for transferring wavelengths, and a system that operates in accordance with the procedure. The system comprises at least one network terminal, each including a switch and a controller. A plurality of wavelength sets are applied to the switch. The controller is arranged to operate the switch such that the switch (a) selects at least one wavelength from at least one of the plurality of wavelength sets, based on electrical monitoring at a port module external to the network terminal, and (b) outputs the at least one wavelength to an output of the at least one network terminal.

A data storage system is disclosed that includes a recirculating loop storing data in motion. The data may be carried by a signal via the loop including one or more satellites or other vessels that return, for example by reflection or regeneration, the signals through the loop. The loop may also include a waveguide, for example an optical fiber, or an optical cavity. Signal multiplexing may be used to increase the contained data. The signal may be amplified at each roundtrip and sometimes a portion of the signal may be regenerated.