Abstract: There are provided a method and system for assessing latency of ciphering end point of secure communication channel. The method comprises: generating a test traffic comprising a series of original data packets, wherein, for each original data packet, size of a given packet is uniquely indicative of the packet's place in a sequence of data packets in the series and enables unique correspondence with a size of the given packet upon its encryption; successively transmitting the original packets to the ciphering end point, whilst associating with respective departure time stamps; receiving encrypted packets from the ciphering end point and associating them with respective arrival time stamps; using a size of a given encrypted packet with a timestamp TSa to identify a size of a matching original packet, its place in the sequence of original packets and, thereby, its departure timestamp TSd, thus giving rise to a plurality of timestamp pairs (TSd; TSa).

Abstract: A method for efficient utilization of a transport capacity provided by an optical transport network includes mapping client signals comprising lower order optical data units into optical data tributary units, each requiring a number of tributary slots of an aggregate payload area having a size corresponding to the available aggregated OPU payload areas of Nx independent higher order optical data units to be transported. The method further includes multiplexing the optical data tributary units into the aggregate payload area. The method further includes mapping the tributary slots of the aggregate payload area into tributary slots provided by the OPU payload areas of the Nx independent higher order Optical data units according to a predefined mapping rule. The method further includes multiplexing the Nx independent optical data units containing the payload areas or transmitting them as optical transport units.

Abstract: A process for using a boot loader to load a set of boot commands to a device such as an embedded system before loading a system application. The process may use a combination of a read-only boot source and a pair of upgradable boot sources. Process also includes a power cycle to put system into a known state. An alternative process may simply use a pair of upgradable boot sources. The processes are resilient to failed updates of an upgradable boot source. After a successful update of an upgradable boot source, a request for a power cycle causes the device to immediately enter a known state and use the updated upgradable boot source.

Abstract: A method, device, and computer-program product of forwarding data packets in a virtual switch is provided. The virtual switch comprises: first, second and third virtual ports for respectively receiving/transmitting: LAN traffic from/to a physical LAN port; secured traffic from/to a physical secured traffic port; and Internet traffic from/to a physical Internet port.

Abstract: Disclosed is a method for determining the link latency of an optical transmission link which includes an end node at each end and one or more pass-through nodes. Each pair of neighboring nodes is connected, at a connection port of each node, by an optical connecting path. Each pass-through node includes an optical pass-through path between its connection ports. The optical connecting paths and optical pass-through paths form an optical link path. A delimiter device includes a delimiter element provided at each connection port of each node. The delimiter element forms a demarcation within the optical link path.

Abstract: A method for removing static differential delays resulting from an independent transport of the client signals of a client signal bundle through an optical transport network, OTN, which comprises OTN mappers mapping received client signals to ODU signals transported to OTN demappers demapping received ODU signals to client signals, wherein a process slave, PS, at the OTN mapper end of said OTN network supplies continuously or in response to a received request information about timing relations between the client signals of said client signal bundle to a process master, PM, at the OTN demapper end of said OTN network used by the process master, PM, to remove the static differential delays between the client signals of the respective client signal bundle.

Abstract: A photonic chip includes a connecting means, a substrate, and a waveguide layer. The photonic integrated waveguide and the optical fiber each have a front end portion. The connecting means includes a groove configured to receive the front end portion of the optical fiber. The groove is essentially U-shaped in its cross section, and the groove has a bottom surface and two inner side surfaces. A least one of both inner side surfaces of the U-shaped groove has a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove. The invention further relates to an optical device which includes a photonic chip and an optical fiber, as well as a method or production of such a photonic chip.

Abstract: A method and apparatus for increasing the operation lifetime of a beam tube are provided. The method includes converting an electrical current output by the beam tube into an intermediate voltage to provide a voltage signal used for changing an electron multiplier polarization voltage applied to an electron multiplier by a power supply unit controlled by an electron multiplier gain control signal generated by a controller. The controller regulates the electrical current output by the beam tube to keep it below a characteristic current threshold by adjusting the electron multiplier gain control signal until it reaches a predefined maximum value. The voltage signal applied to the controller is regulated by increasing the variable gain of a voltage amplifier to compensate for a drop in electrical current output by the beam tube caused by the aging of the electron multiplier until the applied voltage signal reaches a predefined minimum value.

Abstract: The invention relates to a method of determining a time-of-flight of an optical signal between a starting point and a reflection point of an optical path, comprising: supplying to the path at least one optical probing signal; detecting an electrical return signal according to an optical return signal returning from the path in response to a corresponding one of the probing signals using direct detection; deriving at least one receive code sequence by sampling and slicing the return signal using a sampling rate corresponding to a bit rate of a sequence of pulses of the probing signal; determining a correlation function by correlating the transmit code sequence and the at least one receive code sequence; and identifying a main peak of the correlation function that corresponds to the reflection point and a time position of the peak, and determining the time-of-flight as the time position of the peak.

Abstract: A device for producing timing information comprises equipment (101) that extracts first preliminary timing information from a first circular polarized component of a radio signal and second preliminary timing information from a second circular polarized component of the radio signal. The second circular polarized component has an opposite handedness and a time-delay with respect to the first circular polarized component. The device comprises a processing system (102) that produces the timing information based on the first preliminary timing information and/or the second preliminary timing information, and uses stored correction data for reducing the effect of the time-delay on the timing information when using the second preliminary timing information for producing the timing information. Thus, the timing information corresponds to the first preliminary timing information also when the timing information is produced based on the second preliminary timing information.

Abstract: A method and apparatus for performing event-driven diagnostics and/or prognostics of a network behaviour of a hierarchical optical network comprising the steps of recording at least one set of historical multi-level events representing different hierarchy levels of said optical network; mining of machine learned event patterns within the recorded multi-level events; mapping the determined mined event patterns to a multi-level network topology of said optical network and/or to a channel connectivity of channels through said optical network; and matching observed real-time multi-level target events of said optical network with at least one of the previously determined mined event patterns and performing a unified cause and effect analysis of network states and/or network components of said optical network for a recognized matching event pattern using the network topology and/or channel connectivity associated with the matching event pattern.

Abstract: A method for determining a maximum transmission capacity, TCAPMAX-OL, of an optical link, OL, within an optical network includes loading an optical transmission spectrum of the optical link, OL, being partially occupied by at least one data traffic carrying channel, CH, with amplified spontaneous emission, ASE, noise spectrally shaped such that the transmission performance of the optical transmission spectrum fully occupied with data traffic carrying channels, CHs, is matched. The method further includes determining the maximum transmission capacity, TCAPMAX-OL, of the optical link, OL, on the basis of measured link data transported through the optical link, OL, via the at least one data traffic carrying channel, CH.

Abstract: A life cycle network management system for performing life cycle management of distributed network devices, each network device comprising a communication link to a central network management unit and an attached transponder configured to store life cycle data of the network device updated by said network device, wherein if the communication link between the network device and the central network management unit is at least temporarily unavailable the updated life cycle data of the network device stored in the attached transponder is read by an interrogation unit of the life cycle network management system and processed to provide a life cycle management result.

Abstract: Process to associate a set of physical ports on a physical device with a set of software virtual interfaces. Process includes placing the set of software virtual interfaces to be associated with a set of N physical ports in an enabled state which has a first link state when no activation device is connected to a particular software virtual interface and a second link state when an activation device is connected to the particular software virtual interface. Connecting an activation device such as a loopback connector to a physical port to shift the software virtual interface to the second link state to map that particular physical port to that particular software virtual interface.

Abstract: An apparatus and method for optimizing dynamically the performance of an optical network, said apparatus comprising at least one learning engine adapted to update a learning model in response to network metrics of said optical network collected during operation of said optical network, wherein the updated learning model is used to generate channel rank information for network channels; and a recommendation engine adapted to change a network channel throughput, a signal path and/or a spectral location of at least one network channel based on the channel rank information generated by the learning model of said learning engine.

Abstract: A system for proactive traffic restoration in a network includes at least one forecasting engine that models and forecasts traffic patterns of at least one traffic channel along a signal path of the network to provide forecast traffic quality metrics, y. The system further includes at least one time-to-failure, TTF, analyzer that calculates a time-to-failure, TTF, forecast for the traffic channel based on the forecast traffic quality metrics, y. The calculated time-to-failure, TTF, forecast is evaluated to trigger a proactive network traffic restoration.

Abstract: A network edge device may be placed at a location to participate in a VLAN using a specific VLAN ID without expressly programming the network edge device to use that specific VLAN ID. The network edge device is connected to a network to receive ingressing frames from the network and to send egressing frames to the network. The network edge device copies a specific VLAN ID from an ingressing VLAN message into memory and subsequently reads the specific VLAN ID from the memory for use in tagging frames egressing from the network edge device with the specific VLAN ID so that the egressing frames are VLAN conformant. The network edge device may communicate with non-edge devices at the same location as the network edge device.

Abstract: A pluggable aggregation module adapted to be plugged into a network device of an optical network, said pluggable aggregation module comprising optical frontends configured to connect said pluggable aggregation module with a corresponding number of modules to exchange optical signals via optical fibres in legacy signal formats; and an electrical conversion circuit configured to convert the legacy signal formats to an internal signal format used by said network device.

Abstract: A method and apparatus for transporting data through a single optical fiber (SOF) the method comprising the steps of providing (S1) transmission Tx, wavelength division multiplexed, WDM, data channels and reception Rx, wavelength division multiplexed, WDM, data channels having the same frequency grid with frequency gaps between the WDM data channels; frequency shifting (S2) the Tx-WDM data channels and/or the Rx-WDM data channels to avoid spectral overlap between the Tx-WDM data channels and the Rx-WDM data channels; combining (S3) the frequency shifted Tx-WDM data channels and the frequency shifted Rx-WDM data channels; and transporting (S4) data via the combined WDM data channels through said single optical fiber (SOF) in opposite directions.

Abstract: There is provided a method of clock management in a packet data network (PDN) implementing a time-transfer protocol and a clock controller configured to operate therein. The clock controller is configured to: obtain topology data informative of a master clock node and a slave clock node constituting end points of a PTP path in the PDN and further informative of at least part of transit nodes of said PTP path; periodically obtain data informative of queue size and link rate characterizing, during a collection period, the at least part of transit nodes in master-slave (MS) and slave-master (SM) directions; for each collection period, use the obtained queue-related data to estimate queue-induced delay asymmetry of the PTP path; and send the estimated value of queue-induced delay asymmetry to the slave node, the estimated value to be used by a clock residing on the slave node as delay asymmetry correction parameter.