Abstract: A variable optical BPF allows a signal light of a specified wavelength band in a signal light including reference signal lights to pass through. A light receiving unit outputs a level signal indicating a level of the signal light having passed through the variable optical BPF. A control unit refers to a wavelength table held in advance, instructs a wavelength band that passes through the variable optical BPF, and obtains a spectrum of the signal light having passed through the variable optical BPF using the wavelength table and the level signal. The control unit detects a wavelength drift between a center wavelength of the wavelength band instructed to the variable optical BPF to cause the reference signal lights to pass through and center wavelengths of peaks corresponding to the reference signal lights in the spectrum, and updates the wavelength table to corrects the detected wavelength drift.

Abstract: Described is a communication system having a transmitter comprising a first optical module, the first optical module comprising a plurality of Micro-Ring Modulators (MRMs); and a receiver comprising a second optical module, the second optical module comprising a plurality of Micro Ring Resonators (MRRs), wherein the first optical module and the second optical module are connected by an optical waveguide; and at least one comb laser external to an optical co-package comprising the transmitter or the receiver, the at least one comb laser irradiating the optical waveguide, the at least one comb laser emitting light in a plurality of wavelengths, where at least one first MRM and at least one first MRR are adjusted to operate in at least one first wavelengths from the plurality of wavelengths, and at least one second MRM and at least one second MRR are adjusted to operate in at least one second wavelength from the plurality of wavelengths.

Abstract: A modulation device includes: a signal splitter configured to generate: i) an M-bit wide partial signal comprising M more significant bits of an N-bit wide input signal; and ii) an L-bit wide partial signal comprising L less significant bits of the N-bit wide input signal, where L=N?M; a first modulation unit configured to generate a 1-bit wide pulse density modulation signal on the basis of the L-bit wide partial signal; a summation unit configured to generate an M-bit wide summation signal on the basis of the M-bit wide partial signal and the 1-bit wide pulse density modulation signal; and a second modulation unit configured to generate a 1-bit wide pulse width modulation signal on the basis of the M-bit wide summation signal.

Abstract: Methods and systems for load balancing of a communication network are described. Examples of the disclosed methods and systems may be topology agnostic (not specific to a particular network topology). Congestion information is obtained for a plurality of paths between two switches in the communication network. A selection probability is obtained for each path using the congestion information. A flowlet is assigned to a path based on the selection probabilities. Each path may be assigned to a path group, where each path group comprises paths of equal length. The selection probabilities may be computed for each path group and for each path within each path group, and the flowlet may be assigned by selecting a path group based on the selection probabilities of the path groups, and selecting a path within the selected path group.

Abstract: Methods for configuring an optical link in which a distribution of transmission data rates and line rates are configured for a predetermined amount of optical bandwidth to maximize transmission capacity. In these methods, a controller of an optical network obtains input parameters that include a signal-to-noise ratio (SNR) for optical signals and an allocated bandwidth of the optical link, further obtains, for each line rate, a mapping of transmission data rates along a frequency spectrum of the allocated bandwidth compatible with the SNR, and generates a channel plan in which a number of traffic modes and a distribution of a plurality of channels in the allocated bandwidth are set to maximize transmission capacity. The plurality of channels is used for transmitting the signals on the optical link. The controller configures at least one optical network element in the optical network to establish the optical link based on the channel plan.

Abstract: A WDM1r combiner for a PON. The output end of an input waveguide is connected to the input end of a first grating filter, the output end of the first grating filter is connected to the input ends of a first mode filter, a second grating filter, a second mode filter, a connecting waveguide, a third grating filter, a third mode filter, and a fourth grating filter in sequence, and the output end of the fourth grating filter is connected to an output waveguide. The function of the WDM1r combiner for a PON is achieved in the form of cascaded grating filters; different central wavelengths and bandwidths of four channels are obtained by optimizing a grating structure; an on-chip WDM1r combiner which is low in insertion loss and crosstalk and has flat-top response is obtained; the combiner has the advantages of being simple in structure, simple in process, excellent in performance, etc.

Abstract: A hollow core fiber (HCF) link is characterized by structural properties selected to support and sustain light propagation in a fundamental mode and in at least one higher-order mode. Connected to a proximal end of the HCF link, there is a mode coupler configured to couple a data signal into the fundamental mode and to couple an obfuscating signal into the at least one higher-order mode for simultaneous propagation of the data signal and the obfuscating signal on the HCF link, where the obfuscating signal substantially overlaps the data signal in spectral content. At a distal end of the HCF link, there is a mode splitter configured to split a first optical signal detected in the fundamental mode from a second optical signal detected in the at least one higher-order mode.

Abstract: The optical module includes an optical separating element. The optical separating element includes a birefringent material and has a first face and a second face. The first face is configured to receive a signal light and a LO light. The signal light includes a first polarized light and a second polarized light. The first polarized light travels from the first face to the second face in a first direction and is emitted from a first emission spot on the second face. The second polarized light travels from the first face to the second face in a second direction and is emitted from a second emission spot on the second face. The LO light travels from the first face to the second face in the first direction and is emitted from a LO light emission spot which is located between the first emission spot and the second emission spot.

Abstract: Systems, devices, methods, and computer readable medium for transmitting data using polynomials and instantaneous spectral analysis. In and/or prior to the transmitter, a signal may be formed by fitting the data with a polynomial, which is projected onto Cairns series functions. The Cairns series functions are converted into Cairns exponential functions, which are combined based on frequency information to produce the set of sinusoidals with continuously time-varying amplitude, each of the sinusoidals having a different frequency.

Abstract: To generate, in an optical transmission device, a response signal corresponding to executed control even when said optical transmission device does not comprise one or both of a main signal photoelectric conversion function and a main signal optical amplification function, an optical transmission device comprises: an extraction unit that outputs, from a first optical signal including a main signal and a control signal, a signal including control information included in the control signal; a control unit that executes control on the basis of the control information; and a response signal output unit that outputs, according to the control, a response signal in a wavelength band different from the main signal.

Abstract: A method includes measuring a first set of photon-event data collected from a first crosstalk-monitoring zone of an optical receiver during a first period of time of flight ranging, measuring a second set of photon-event data collected from a second crosstalk-monitoring zone of the optical receiver during the first period of time of flight ranging, and generating a first dynamic crosstalk compensation value for a first histogram region of the optical receiver using the first set of photon-event data, the second set of photon-event data, and a native crosstalk compensation value for the first histogram region of the optical receiver.

Abstract: A method may include directing transmission of a first optical noise signal along a frequency channel of an optical network at a first power level. The first optical noise signal may include a notch at a frequency in the frequency channel. The method may also include while transmission of the first optical noise signal occurs along the frequency channel, obtaining a measurement of a first noise level at the frequency and obtaining a measurement of a second noise level at the frequency. The frequency channel may include a second power level when the measurement of the second noise level is obtained and the second power level may be different than the first power level. The method may further include estimating a noise level of an optical data signal transmitted along the frequency channel based on the first noise level and the second noise level.

Abstract: Optical sensors and particularly gimbaled optical sensors transmit an active signal at a given wavelength(s) and receive passive signals over a range of wavelengths and the active signal in a common aperture. The sensor includes a Tx/Rx Aperture Sharing Element (ASE) configured with an annular region that couples an active signal having a ring-shaped energy distribution to the telescope for transmission and a center region that couples the passive emissions and the returned active signal to the detector. A beam shaping element such as an Axicon lens, LCWG, Risley Prism, Unstable Optical Resonator or MEMS MMA may be used to form or trace the ring-shaped active signal onto the annular region of the ASE. A focusing optic may be used to reduce the divergence of the active signal so that it is collimated or slightly converging when transmitted such that the returned active signal approximates a spot. A filter wheel may be positioned behind the ASE to present separate passive and active images to the detector.

Abstract: Proposed is a method for transmitting signals in visible light communications. The method for transmitting signals in visible light communications comprises: a step of receiving interference information from a receiving end; a step of transmitting a constellation set index to the receiving end; and a step of transmitting, to the receiving end, signals modified on the basis of the constellation set index. Meanwhile, the constellation set index may be selected on the basis of the received interference information.

Abstract: Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously overcome problems encountered when operating DFOS systems over operational telecommunications facilities namely, cross-phase modulation, and uneven amplitude profiles through the use of a novel constant amplitude coded DFOS employing suppressed out-of-band signaling.

Abstract: Methods for configuring an optical link in which a distribution of transmission data rates and line rates are configured for a predetermined amount of optical bandwidth to maximize transmission capacity. In these methods, a controller of an optical network obtains input parameters that include a signal-to-noise ratio (SNR) for optical signals and an allocated bandwidth of the optical link, further obtains, for each line rate, a mapping of transmission data rates along a frequency spectrum of the allocated bandwidth compatible with the SNR, and generates a channel plan in which a number of traffic modes and a distribution of a plurality of channels in the allocated bandwidth are set to maximize transmission capacity. The plurality of channels is used for transmitting the signals on the optical link. The controller configures at least one optical network element in the optical network to establish the optical link based on the channel plan.

Abstract: Described are optical fibers, e.g., for use in stress-sensing or shape-sensing applications, that use overlapping grating configurations with chirped gratings to facilitate strain delay registration. In accordance with various embodiments, a fiber core may, for instance, have two overlapping sets of chirped gratings that differ in the direction of the chirp between the first and second sets, or a set of chirped gratings overlapping with a single-frequency grating. Also described are strain sensing systems and associated computational methods employing optical fibers with overlapping gratings.

Abstract: The present disclosure relates to methods for transmitting or receiving one on more signals in a system where multiple numerologies are used, and for adapting, selecting, or determining the ON/OFF mask for said signals depending on the numerology used for the respective signals, and based on the location of critical signals close to the transient periods. The disclosure also relates to corresponding devices and to a computer program for executing the proposed methods, and to a carrier containing said computer program. Further, embodiments relating to a host computer and activities therein, is also comprised in the current disclosure.

Abstract: Described are optical fibers, e.g., for use in stress-sensing or shape-sensing applications, that use overlapping grating configurations with chirped gratings to facilitate strain delay registration. In accordance with various embodiments, a fiber core may, for instance, have two overlapping sets of chirped gratings that differ in the direction of the chirp between the first and second sets, or a set of chirped gratings overlapping with a single-frequency grating. Also described are strain sensing systems and associated computational methods employing optical fibers with overlapping gratings.

Abstract: An optical transmission system includes: a terminal station device that transmits a wavelength multiplexed optical signal resulting from multiplexing an optical signal and dummy light; and an optical add-drop multiplexer that receives respective wavelength multiplexed optical signals transmitted from a plurality of the terminal station devices and performs add-drop processing on the wavelength multiplexed optical signals. The dummy light has a wavelength arrangement in which adjacent wavelengths are arranged with equal spacing, and the wavelength arrangement of the dummy light differs between the terminal station devices.

Abstract: Methods and systems for monitoring an optical network are described. An optical device may receive a data signal. The optical device may send the data signal to a test port. A measuring device may measure characteristics associated with the data signal.

Abstract: A defect detecting device includes an illumination that irradiates a measuring object with illumination light, an imager that images the illumination light reflected by the measuring object, and a detector that detects a defect at a surface of the measuring object based on a captured image obtained by imaging the illumination light by the imager. The captured image includes a plurality of spectral images having different spectral wavelengths, and the detector detects a diffuse reflection region by which the illumination light is diffusely reflected based on the plurality of spectral images, and determines a size of the defect based on the spectral wavelength of the spectral image in which the diffuse reflection region is detected.

Abstract: Various implementations of network devices disclosed herein provide a method routing a data packet in an optical domain, the data packet including a first component or header and second component or routing information, stripping the first component or header from the data packet using a silicon photonic component, processing the first component or header in an electrical domain, and communicating the data packet without the first component or header to an optical delay line.

Abstract: A spectrometer includes a substrate; a slit which is provided on the substrate and through which light is incident onto the substrate; a metasurface including nanostructures that is configured to reflect and focus the light incident thereon through the slit, at different angles based on respective wavelengths; and a sensor which is provided on one side of the substrate that is opposite to another side of the substrate at which the metasurface is disposed, and configured to receive the light from the metasurface.

Abstract: A co-packaged optical-electrical chip can include an application-specific integrated circuit (ASIC) and a plurality of optical modules, such as optical transceivers. The ASIC and each of the optical modules can exchange electrical signaling via integrated electrical paths. The ASIC can include Ethernet switch, error correction, bit-to-symbol mapping/demapping, and digital signal processing circuits to pre-compensate and post-compensate channel impairments (e.g., inter-channel/intra-channel impairments) in electrical and optical domains. The co-packaged inter-chip interface can be scaled to handle different data rates using spectral efficient signaling formats (e.g., QAM-64, PAM-8) without adding additional data lines to a given design and without significantly increasing the power consumption of the design.

Abstract: A method of transmitting optical data includes providing a plurality of light sources in a transmission system, transmitting a data signal with data to be transmitted to the transmission system, decomposing the data signal in the transmission system into N different sub-signals, wherein N is a natural number with N?2, and controlling the light sources based on the sub-signals such that each of the light sources emits light according to one of the sub-signals and the light emitted overall by the light sources transmits the data.

Abstract: In a method for detecting loops between ports in a point-to-multipoint Gigabit Passive Optical Network, GPON, based access network, the GPON based access network may comprise an Optical Line Terminal, OLT, coupled with a plurality of Optical Network Units, ONUs. Each ONU may comprise a plurality of ports. The method may comprise a step of transmitting loop detection frames from a source port and a step of monitoring traffic that is received at a destination port. If a loop detection frame is received at the destination port, the method may further comprise a step of blocking traffic transmission and reception at the destination port.

Abstract: An information flow control device has: a first network interface card on a transmission side, the first network interface card including first and second transceivers, each of the first and second transceivers having a transmit port and a receive port; and a second network interface card on a receiving side, the second network interface card including at least one receive port. A first data connection segment connects the first transceiver transmit port to the second transceiver receive port, a second data connection segment connects the second transceiver transmit port to the first transceiver receive port, and a third data connection segment connects the first transceiver transmit port to the receive port of the second network interface card. The first and second segments provide continuity, while the third segment provides one-way data transfer. The first and second transceivers are replaceable with third and fourth transceivers to provide different throughput.

Abstract: Systems and methods for measuring accumulated power losses over a fiber link are described in the present disclosure. According to one embodiment, a method includes the step of measuring accumulated losses over a fiber link. The method also includes the step of at least partially compensating for the measured accumulated losses. In response to determining that there is a compensation shortfall with respect to the accumulated losses, the method includes the step of transmitting the compensation shortfall to one or more downstream controllers.

Abstract: The function of each component of an optical transmission device is as follows. The wavelength selecting means has a means for selecting an optical signal, and a means for outputting a signal after adjusting the signal level. The optical amplifying means amplifies the wavelength multiplexed signal having the adjusted signal level. The measuring means measures the spectrum of the amplified wavelength multiplexed signal. The setting means sets a spectrum shape, which serves as a reference of the wavelength multiplexed signal to be outputted to the transmission line, as output spectrum setting information. The control means compares the measured spectrum with the output spectrum setting information and determines the attenuation amount when adjusting the signal level for each wavelength of the wavelength multiplexed signal in the wavelength selecting means. The wavelength selecting means adjusts the signal level on the basis of the determined attenuation amount.

Abstract: An information flow control device has: a first network interface card on a transmission side, the first network interface card including first and second transceivers, each of the first and second transceivers having a transmit port and a receive port; and a second network interface card on a receiving side, the second network interface card including at least one receive port. A first data connection segment connects the first transceiver transmit port to the second transceiver receive port, a second data connection segment connects the second transceiver transmit port to the first transceiver receive port, and a third data connection segment connects the first transceiver transmit port to the receive port of the second network interface card. Interconnection of the first and second transceivers provides continuity while connection of the first transceiver transmit port and the receive port of the second network interface card enables hardware-enforced one-way data transfer.

Abstract: Disclosed herein is a method of assigning a wavelength to a given light path in a wavelength switched optical network, as well as a corresponding routing engine and computer program. The method comprises the following step.

Abstract: Disclosed is an electrical module adapted to operatively connect to a transmission line. The electrical module includes a connection point adapted to connect to a network device. The electrical module is configured to receive a composite signal from the transmission line, the composite signal including a data component and a power component, and to separate the composite signal to extract the data component and the power component. The electrical module is further configured to transmit data to the network device through the connection point, and to supply power to the network device through the connection point. Also disclosed is a telecommunication system and method.

Abstract: An apparatus for measuring optical power includes a first component configured to at least one of multiplex or demultiplex between a first composite optical waveguide and at least a first intermediate optical waveguide and a second intermediate optical waveguide. The apparatus further includes a second component configured to at least one of multiplex or demultiplex between a second composite optical waveguide and at least the first intermediate optical waveguide and the second intermediate optical waveguide. The first and second components have complimentary isolation levels. The apparatus further includes a first optical coupler positioned along the first intermediate optical waveguide and a second optical coupler positioned along the second intermediate optical waveguide. The apparatus further includes a first photodetector, a second photodetector, a first measurement device, and a second measurement device.

Abstract: An optical network is described that has a first ROADM node, a second ROADM node, and an optical transmission line establishing optical communication between the first ROADM node and the second ROADM node. The optical transmission line including an in-line amplifier node having a total input power and a total output power. The in-line amplifier node has a first monitoring tool configured to measure input optical power of the in-line amplifier node, and a second monitoring tool configured to measure output optical power of the in-line amplifier node. A software defined L0 network controller has circuitry configured to receive the optical power measured by the first and second monitoring tools from the in-line amplifier node, and to configure at least one of a gain and a gain tilt of the in-line amplifier node.

Abstract: Examples of a polarization independent optical device are described. One example polarization independent optical device includes an input/output preprocessing optical path and M add/drop optical paths. Any add/drop optical path can be configured to drop a first QTE and a first PTE that meet a resonance condition of a microring included in the add/drop optical path such that each add/drop optical path can be configured to drop a desired optical signal. Any add/drop optical path can also be configured to transmit an input optical signal to the input/output preprocessing optical path. Therefore, when any of the M add/drop optical paths is configured to drop a desired optical signal, another add/drop optical path can be configured to add a desired optical signal.

Abstract: Various implementations of network devices disclosed herein provide a method routing a data packet in an optical domain, the data packet including a first component or header and second component or routing information, stripping the first component or header from the data packet using a silicon photonic component, processing the first component or header in an electrical domain, and communicating the data packet without the first component or header to an optical delay line.

Abstract: A laser-based device or sensor includes: a first laser transmitter having a first self-mix carrier frequency; a second laser transmitter having a second, different, self-mix carrier frequency; a first monitor photodiode to receive a first optical signal from the first laser transmitter, and to output a first electric signal; a second monitor photodiode to receive a first optical signal from the second laser transmitter, and to output a second electric signal; an electric connection to connect together the first electric signal and the second electric signal, forming a combined electric signal; a single laser receiver to receive the combined electric signal and to generate from it a spectrum that corresponds to both (i) self-mix signal of the first laser transmitter, and (ii) self-mix signal of the second laser transmitter. Alternatively, a single monitor photodiode is used, receiving self-mix signals from multiple laser transmitters, and outputting a single electric signal to a single laser receiver.

Abstract: A system and method consistent with the present disclosure provides for automated line monitoring system (LMS) baselining that enables capturing and updating of operational parameters specific to each repeater and associated undersea elements based on high loss loopback (HLLB) data. The captured operational parameters may then be utilized to satisfy queries targeting specific undersea elements in a Command-Response (CR) fashion. Therefore, command-response functionality may be achieved without the added cost, complexity and lifespan issues related to deploying undersea elements with on-board CR circuitry. As generally referred to herein, operational parameters include any parameter that may be derived directly or indirectly from HLLB data. Some example non-limiting examples of operational parameters include span gain loss, input power, output power, gain, and gain tilt.

Abstract: A near eye display (NED) that includes an illumination source including a photonic array. The photonic array includes at least one waveguide that divides light from one or more emitters into a number of channels, and outputs the divided light using a plurality of outputs. An optical switching assembly includes a one or more input ports and a plurality of output ports. The optical switching assembly is configured to map light from the one or more input ports to the plurality of outputs. In various embodiments, the optical switching assembly is additionally configured to control the relative illumination, timing, and phase of light produced by each of the plurality of outputs. The optical switching assembly selectively outputs some or all of the incoupled light via output ports of the plurality of output ports in accordance with instructions from a controller, the outcoupled light forming a light pattern.

Abstract: An optics module sends, to a host module, a pin signal indicating that an optics module is plugged into the host module, wherein the optics module is configured to operate at at least a first data rate and a second data rate. The optics module receives, from the host module, an indication of a host data rate. The optics module determines whether there is clock and data recovery loss of lock between the first data rate and a host data rate. If it is determined that there is clock and data recovery loss of lock between the first data rate and the host data rate, the optics module initializes at the second data rate if the second data rate matches the host data rate.

Abstract: An optical data transmitter in which surface-coupled reflective electro-absorption modulators are placed into different interferometer arms and operated in a manner that enables the optical data transmitter to transmit an optical output signal modulated using PAM, QPSK, or QAM modulation. In some embodiments, the optical data transmitter is configured to generate a PDM optical output signal by using two such interferometers and a quarter-wavelength plate configured to cause the output polarizations of the two interferometers to be mutually orthogonal. The electro-absorption modulators are surface-coupled in the sense that, in operation, each of these devices receives input light and outputs modulated light along a direction that is substantially orthogonal to the main plane of the device.

Abstract: A distribution system and reception apparatus, and methods thereof, are provided for broadcasting and receiving a plurality of first services from a plurality of different broadcast providers, which broadcast a plurality of second services over a plurality of different broadcast channels, on a transition broadcast channel that is different from the plurality of different broadcast channels. The system includes at least one receiver and a transmitter. The at least one receiver is configured to receive the plurality of first services from the plurality of different broadcast providers. The transmitter is configured to broadcast the plurality of first services over the transition broadcast channel.

Abstract: A method is provided that includes accessing, by a debugging device associated with an external user device, (i) a serial console of a hardware network device, and (ii) a management Ethernet port of the hardware network device. The method includes providing, by the debugging device, (i) a serial console interface from the serial console of the hardware network device to the external user device, and (ii) a management Ethernet interface from the management Ethernet port of the hardware network device to the external user device. The method includes receiving, by serial console interface and the management Ethernet interface of the debugging device, user input from the external user device. The method includes sending, using a hardware bypass in the debugging device. Ethernet management traffic from the hardware network device to the external user device through an internal network, responsive to the debugging device improperly operating.

Abstract: A system for mapping a multilayer network having a server layer and a client layer is provided. The system includes a framework configured for comparing information obtained from a first traffic counter of a client port to information obtained from a second traffic counter of a server port to thereby determine if the client port and the server port are linked.

Abstract: The present techniques are related to an apparatus for an MEMS LED zoom. The apparatus for includes an LED light source and a collimation lens. The collimation lens to collimate light from the LED light source. The apparatus is also to include an active lens. The active lens to adjust the collimated light from the collimation lens.

Abstract: Methods and associated computer program products for testing optical transmitters are provided. The method includes applying a first constant current input to at least one optical transmitter of a plurality of optical transmitters supported by a substrate where each substrate is received by a socket of a testing board. The method includes monitoring a first output voltage and a first operating temperature of the optical transmitter and includes determining a first voltage pass state or a first voltage fail state of the optical transmitter. The method also includes determining a first temperature pass state or a first temperature fail state of the optical transmitter. The method includes determining a first pass state for the optical transmitter in an instance in which the first voltage pass state and the first temperature pass state are determined.

Abstract: Computer-implemented systems and methods for visually presenting spectrum usage of optical spectrum in an optical network include obtaining spectrum data which defines spectrum usage of optical spectrum associated with the optical network including a plurality of nodes interconnected by a plurality of links; and displaying a circular histogram to visually illustrate the spectrum usage based on the spectrum data, wherein each segment of the circular histogram represents an associated portion of the optical spectrum and a visual indicator in each segment represents usage of the associated portion.

Abstract: A method may include causing a signal to be transmitted that includes a plurality of wavelengths. The signal may be transmitted via an optical fiber that is associated with a particular wavelength. The particular wavelength may be included in the plurality of wavelengths. The method may include filtering the signal, based on the particular wavelength, to generate a filtered signal. The filtered signal may include the particular wavelength. The method may include detecting the filtered signal in association with the optical fiber. The method may include determining the particular wavelength based on the filtered signal. The method may include storing or providing information identifying at least one of the particular wavelength, the optical fiber, or a transmitter that transmitted the signal.

Abstract: The present invention relates to distributing and relaying a signal from two or more femtocells to several antennas by using a UTP line. That is, the present invention relates to a dual-band UTP femto distribution/relay device for combining two or more femtocells into a single signal, transmitting the signal through a UTP cable and wirelessly transmitting and receiving the signal remotely with a terminal.