Examples described herein relate to link training between network connected devices. In some examples, an amount to extend link training is determined. The amount to extend link training can be determined by: receiving, by a receiver in a first device, signals over a lane from a transmitter in a second device, the signals indicating capability to extend link training time and amount to extend link training time; determining, at the first device, a link training time based on a default link training time and an amount to extend link training time; and performing link training based on the determined link training time. In some examples, the determined amount is highest common denominator of the received identified capability and transmitted indicated capability. In some examples, if the received communication indicates no ability to extend link training time, the link training time is a default link training time. In some examples, the signals indicating capability to extend link training time and amount to extend link training time comprise an IEEE 802.3 compatible Next Page.

The present disclosure is directed to systems and methods for calculating a modal time delay and a modal bandwidth. For example, a method may include: transmitting an intensity-modulated light through a mode conditioner to generate a mode-conditioned intensity-modulated light; transmitting the mode-conditioned intensity-modulated light through an optical fiber under test (FUT) to excite a plurality of modes of the optical FUT; converting the mode-conditioned intensity-modulated light transmitted through the optical FUT into an electrical signal; measuring, based on the electrical signal, a transfer function or a complex transfer function of the optical FUT based on at least on one pair of the plurality of modes; calculating a modal delay time of the optical FUT based on the transfer function or the complex transfer function; and calculating a modal bandwidth of the optical FUT based on the modal delay time, the modal bandwidth being calculated for any given launch conditions of the plurality of modes.

Systems and methods for optically initiated information collection for network connected devices are provided. In one embodiment, a device comprises: at least one service port to connect a cable to the device; an optical information interface comprising: an optical information interface management function executed by a processor coupled to a memory; an optical information interface database that stores information associated with the device; and an optical emitter controller in communication with the optical information interface management function; wherein the optical information interface management function receives from the optical information interface database a set of information selected for optical broadcast; and wherein the optical emitter controller varies an optical output of at least one optical emitter to modulate the set of information selected for optical broadcast onto an optical signal generated by the at least one optical emitter.

An optical system includes a transmitter including transmitter circuitry configured to cause transmission of a transmitted optical signal over a fiber link on an X polarization and a Y polarization; and a receiver including receiver circuitry configured to receive a received optical signal from the fiber link on the X polarization and the Y polarization, wherein the transmitter circuitry is configured to cause State of Polarization (SOP) changes on the X polarization and the Y polarization for a test of the fiber link. The transmitter circuitry and the receiver circuitry are built-in with the transmitter and the receiver, respectively, for performance of the test.

Examples described herein relate to determining whether a device can re-train settings of one or more components of another device. Some examples include conducting link re-training by: receiving, by a receiver in a first device, signals over a lane from a transmitter in a second device, the signals comprising a first communication identifying capability to re-train a link; transmitting, from the first device, a second communication including one or more components of a second device with capability to be adjusted and a request to modify one or more parameters of the one or more components; and receiving, at the first device, a third communication identifying a status of re-training. In some examples, the one or more components comprise an equalizer and the one or more parameters comprises at least one tap setting. In some examples, the one or more parameters comprise a precursor, main cursor or post-cursor equalization setting.

Techniques are disclosed for aligning an optical transmitter with an optical receiver for a line-of-sight communications link, wherein the optical transmitter comprises a laser array emitter, the laser array emitter comprising a plurality of laser emitting regions, wherein each of a plurality of the laser emitting regions is configured to emit laser light in a different direction such that the laser array emitter is capable of emitting laser light in a plurality of different directions. The system can run produce emissions from different laser emitting regions until a laser emitting region that is in alignment with the optical receiver is found. This aligned laser emitting region can then be selected for use to optically communicate data from the optical transmitter to the optical receiver.

A monitorable hollow core (HC) optical fiber comprises one or more hollow core anti-resonant fiber (HC-ARF) segments and one or more monitoring segments alternatingly connected with the HC-ARF segments, and where each monitoring segment comprises one or more non-HC-ARF constituents. A method for monitoring a monitorable HC optical fiber comprises transmitting one or more first optical signals on the monitorable HC optical fiber, detecting one or more second optical signals on the monitorable HC optical fiber, and monitoring one or more optical properties of the monitorable HC optical fiber using the first optical signals and the second optical signals, where the monitoring is enabled as a result of interactions between the first optical signals and the non-HC-ARF constituents of the monitoring segments.

A test instrument for providing an optics troubleshooting technique of an optical transceiver is disclosed. The test instrument may comprise a processor and a memory, which when executed by the processor, performs the optics troubleshooting technique. The optics troubleshooting technique may include identifying a test signal from the optical transceiver. The optics troubleshooting technique may include determining signal power associated with the signal. The optics troubleshooting technique may further include applying one or more expert mode settings. In some examples, the one or more expert mode settings may be applied in a predefined order until an acceptable BER result is achieved over a predefined test period. In this way, test instrument may determine which of the one or more expert mode settings is responsible for the acceptable BER result.

A monitorable hollow core (HC) optical fiber comprises one or more hollow core anti-resonant fiber (HC-ARF) segments and one or more monitoring segments alternatingly connected with the HC-ARF segments, and where each monitoring segment comprises one or more non-HC-ARF constituents. A method for monitoring a monitorable HC optical fiber comprises transmitting one or more first optical signals on the monitorable HC optical fiber, detecting one or more second optical signals on the monitorable HC optical fiber, and monitoring one or more optical properties of the monitorable HC optical fiber using the first optical signals and the second optical signals, where the monitoring is enabled as a result of interactions between the first optical signals and the non-HC-ARF constituents of the monitoring segments.

A system includes an optical transmitter including a transmitter Phase Lock Loop (PLL) circuit; an optical receiver connected to the optical transmitter and including a receiver PLL circuit; and circuitry configured to inject a test stimulus to a clock causing jitter in one of the transmitter PLL circuitry and the receiver PLL circuit, wherein the test stimulus is set for characterizing the jitter tolerance of optical receiver. As well, a circuit that injects SOP transient at the transmitter is included. It is configured to test the tolerance of optical receiver to handle fast change in the SOP state. The optical receiver is configured to determine if the system is operational at a jitter value due to the test stimulus based on compliance to one or more thresholds including any of a target Bit Error Rate, a Forward-Error-Correction (FEC) hit, and a jitter Root Mean Square (RMS).