Abstract: A method includes mapping, by an optical transceiver, a received first OTU4 signal to a first FlexO frame without interleaving the first OTU4 signal into an ODUC signal prior to mapping the first OTU4 signal to the first FlexO frame. The method also includes communicating, by the optical transceiver, the first FlexO frame with the mapped first OTU4 signal to a coherent DSP over a first FOIC.

Abstract: A method includes mapping, by an optical transceiver, a received first OTU4 signal to a first FlexO frame without interleaving the first OTU4 signal into an ODUC signal prior to mapping the first OTU4 signal to the first FlexO frame. The method also includes communicating, by the optical transceiver, the first FlexO frame with the mapped first OTU4 signal to a coherent DSP over a first FOIC.

Abstract: 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.

Abstract: 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.

Abstract: A method of obtaining a measure of asymmetry between optical fibers of a forward and reverse paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes receiving, at first and second arrival times, from a first optical network device, a first optical signal transmitted on a first optical fiber and a second optical signal transmitted on a second optical fiber, calculating a first time difference between the second arrival time and the first arrival time. The method includes determining a measure of asymmetry between the first optical fiber and the second optical fiber based on the first time difference and a second time difference between a first time of transmission by the first optical network device of the first optical signal and a second time of transmission by the first optical network device of the second optical signal.

Abstract: A first device receives a first container frame having a payload of a first length. The payload of the container frame includes multiple optical transport unit (OTU) frames, each of which includes an optical data unit (ODU) frame and a sequence of forward error correction (FEC) bits for the ODU frame. Each OTU frame is associated with a first sequence of error-identifying bits. The first device determines, for each OTU frame, a second sequence of error-identifying bits, and forms a second container frame including the OTU frames, the first sequences of error-identifying bits, and the second sequences of error-identifying bits. The first device transmits the second container frame to a second device.

Abstract: A method of obtaining a measure of asymmetry between optical fibers of a forward and reverse paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes receiving, at first and second arrival times, from a first optical network device, a first optical signal transmitted on a first optical fiber and a second optical signal transmitted on a second optical fiber, calculating a first time difference between the second arrival time and the first arrival time. The method includes determining a measure of asymmetry between the first optical fiber and the second optical fiber based on the first time difference and a second time difference between a first time of transmission by the first optical network device of the first optical signal and a second time of transmission by the first optical network device of the second optical signal.

Abstract: In one embodiment an apparatus, method, and system is described, the embodiment an apparatus, method including receiving a stream of data frames at an input interface, the data frames one of including security frames, or being included in security frames, wherein the security frames include payload data, performing forward error correction on the data frames a forward error correction (FEC) decoder, buffering received data frames at a buffer and blanker engine and building a complete security frame of the received data frames, determining whether or not to suppress taking a consequent action based on a frequency of authentication errors at an authentication engine, wherein the consequent action to be taken or suppressed, when taken, is taken upon payload data of one or more security frames including a data frame upon which an authentication error occurred. Related apparatus, methods and systems are also described.

Abstract: A method of obtaining a measure of asymmetry between optical fibers of a forward and reverse paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes receiving, at first and second arrival times, from a first optical network device, a first optical signal transmitted on a first optical fiber and a second optical signal transmitted on a second optical fiber, calculating a first time difference between the second arrival time and the first arrival time. The method includes determining a measure of asymmetry between the first optical fiber and the second optical fiber based on the first time difference and a second time difference between a first time of transmission by the first optical network device of the first optical signal and a second time of transmission by the first optical network device of the second optical signal.

Abstract: A method divides data traffic into multiple optical transport units formatted according to an optical transport network (OTN) standard. The multiple optical transport units include a master optical network unit and one or more slave optical network units. Each optical network unit includes overhead and a payload. The overhead includes used overhead specifically defined in the OTN standard and unused overhead not specifically defined in the OTN standard. The method encrypts each optical network unit with a respective one of multiple encryption keys, defines security control parameters identifying the multiple encryption keys, and inserts the security control parameters into the unused overhead of a first slave optical network unit among the one or more slave optical network units. The method transmits the optical network units in encrypted form.

Abstract: A first device receives a first container frame having a payload of a first length. The payload of the container frame includes multiple optical transport unit (OTU) frames, each of which includes an optical data unit (ODU) frame and a sequence of forward error correction (FEC) bits for the ODU frame. Each OTU frame is associated with a first sequence of error-identifying bits. The first device determines, for each OTU frame, a second sequence of error-identifying bits, and forms a second container frame including the OTU frames, the first sequences of error-identifying bits, and the second sequences of error-identifying bits. The first device transmits the second container frame to a second device.

Abstract: A method of measuring lengths of optical fibers on forward and return paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes calculating, by a first optical network device, a first propagation delay of a first optical signal transmitted at a first wavelength on a first optical fiber to the first optical network device from a second optical network device and a second propagation delay of a second optical signal transmitted at a second wavelength on the first optical fiber to the first optical network device from the second optical network device. The second wavelength is different from the first wavelength. The method further includes determining, by the first optical network device, a first length of the first optical fiber based on the first propagation delay and the second propagation delay.

Abstract: A first device receives, over a first communications link, a container frame having a payload of a first length. The payload of the container frame includes multiple optical transport unit (OTU) frames of a second length. The first length is not a multiple of the second length. Each of the OTU frames includes an optical data unit (ODU) frame, a sequence of forward error correction (FEC) bits for the ODU frame, and a sequence of error-identifying bits for the ODU frame. The first device determines, based on the sequences of error-identifying bits, a performance of the first communications link.

Abstract: A first device receives, over a first communications link, a container frame having a payload of a first length. The payload of the container frame includes multiple optical transport unit (OTU) frames of a second length. The first length is not a multiple of the second length. Each of the OTU frames includes an optical data unit (ODU) frame, a sequence of forward error correction (FEC) bits for the ODU frame, and a sequence of error-identifying bits for the ODU frame. The first device determines, based on the sequences of error-identifying bits, a performance of the first communications link.

Abstract: In one embodiment an apparatus, method, and system is described, the embodiment an apparatus, method including receiving a stream of data frames at an input interface, the data frames one of including security frames, or being included in security frames, wherein the security frames include payload data, performing forward error correction on the data frames a forward error correction (FEC) decoder, buffering received data frames at a buffer and blanker engine and building a complete security frame of the received data frames, determining whether or not to suppress taking a consequent action based on a frequency of authentication errors at an authentication engine, wherein the consequent action to be taken or suppressed, when taken, is taken upon payload data of one or more security frames including a data frame upon which an authentication error occurred. Related apparatus, methods and systems are also described.

Abstract: In one embodiment an apparatus, method, and system is described, the embodiment an apparatus, method including receiving a stream of data frames at an input interface, the data frames one of including security frames, or being included in security frames, wherein the security frames include payload data, performing forward error correction on the data frames a forward error correction (FEC) decoder, buffering received data frames at a buffer and blanker engine and building a complete security frame of the received data frames, determining whether or not to suppress taking a consequent action based on a frequency of authentication errors at an authentication engine, wherein the consequent action to be taken or suppressed, when taken, is taken upon payload data of one or more security frames including a data frame upon which an authentication error occurred. Related apparatus, methods and systems are also described.

Abstract: An optical frame is received over an optical link within an optical network. The optical frame contains a payload of aggregated data, an alignment value, and a bit interleaved parity value. The content of the optical frame is aligned based on the alignment value. The bit interleaved parity value is monitored. In response to the monitoring, a transmission quality of the transmission link is determined.

Abstract: In one embodiment an apparatus, method, and system is described, the embodiment an apparatus, method including receiving a stream of data frames at an input interface, the data frames one of including security frames, or being included in security frames, wherein the security frames include payload data, performing forward error correction on the data frames a forward error correction (FEC) decoder, buffering received data frames at a buffer and blanker engine and building a complete security frame of the received data frames, determining whether or not to suppress taking a consequent action based on a frequency of authentication errors at an authentication engine, wherein the consequent action to be taken or suppressed, when taken, is taken upon payload data of one or more security frames including a data frame upon which an authentication error occurred. Related apparatus, methods and systems are also described.

Abstract: A method generates, from an input data stream, multiple lanes of a physical coding sublayer (PCS) signal. The method converts the data stream to a sequence of bit blocks, and periodically inserts into the sequence of bit blocks an alignment marker (AM) group including multiple individual alignment markers for respective ones of the multiple lanes. The method adds security protection to each bit block according to a security protocol to produce a sequence of protected bit blocks, and modifies each AM group with security information to be used by the security protocol to remove the security protection added to the sequence of protected bit blocks. The method applies forward error correction to the sequence of protected bit blocks and the modified AM groups to produce forward error correction codewords, and produces the multiple lanes from the codewords. The method transmits the multiple lanes over an optical link.

Abstract: A method divides data traffic into multiple optical transport units formatted according to an optical transport network (OTN) standard. The multiple optical transport units include a master optical network unit and one or more slave optical network units. Each optical network unit includes overhead and a payload. The overhead includes used overhead specifically defined in the OTN standard and unused overhead not specifically defined in the OTN standard. The method encrypts each optical network unit with a respective one of multiple encryption keys, defines security control parameters identifying the multiple encryption keys, and inserts the security control parameters into the unused overhead of a first slave optical network unit among the one or more slave optical network units. The method transmits the optical network units in encrypted form.