Abstract: A transmitter includes at least three tunable laser sources, an optical multiplexer, and a processor. The at least three tunable laser sources are configured to receive respective data streams, and to output respective Tx light beams at different respective carrier frequencies, modulated with the respective data streams. The optical multiplexer is configured to combine the multiple Tx light beams to produce a combined beam formed of the modulated Tx light beams at the different carrier frequencies, and to transmit the combined beam over an optical fiber. The processor is configured to receive a notification indicative of an interference occurring due to Four-Wave Mixing (FWM) in the optical fiber, and to modify at least one of the carrier frequencies responsively to the notification in order to mitigate the interference due to FWM.

Abstract: In a communication network operating according to a communication protocol that defines a link establishment procedure having i) a negotiating procedure and ii) a training procedure, a first communication device performs the link establishment procedure with a second communication device. During the negotiating procedure, the first communication device negotiates one or more new parameter values for the link establishment procedure that are different than one or more mandated parameter values specified by the communication protocol. During the link establishment procedure, the first communication device uses the one or more new parameter values instead of using the one or more mandated parameter values specified by the communication protocol.

Abstract: Timestamp circuitry of a network device modifies a packet by embedding a future timestamp in the packet to generate a timestamped packet. The future timestamp corresponds to a transmit time that occurs after the timestamp circuitry embeds the future timestamp in the packet. The timing information is added to the packet and the packet is then transferred to transmitter circuitry of the network device via a communication link, internal to the network device, that operates according to a media independent communication interface. Time gating circuitry of the transmitter circuitry i) holds the timestamped packet from proceeding to a network link coupled to the network device prior to a current time reaching the transmit time, and ii) releases the timestamped packet for transmission via the network link in response to the current time reaching the transmit time.

Abstract: In a network having at least one slave node including a slave clock, a method of adjusting the slave clock relative to a master clock of a master node includes, at the slave node, correcting a time of day of the slave clock using (a) a slave pulse signal having a known slave pulse rate, (b) a time-of-day counter of the slave node, and (c) a master pulse signal, based on values of the slave clock at nearest corresponding edges of the slave pulse signal and the master pulse signal, and correcting a frequency of the slave clock using the slave pulse signal, a clock signal of the slave node, and the master pulse signal, based on values of the slave clock at nearest corresponding edges of the master pulse signal. No other clock signal from outside the slave node is used for the corrections.

Abstract: An integrated Circuit (IC) for use in a network device includes a receiver and a Link Quality Estimation Circuit (LQEC). The receiver is configured to receive a signal over a link and to process the received signal. The LQEC is configured to predict a link quality measure indicative of communication quality over the link in the future, by analyzing at least one or more settings of circuitry of the receiver, and to initiate a responsive action depending on the predicted link quality measure.