Abstract: A fill level control apparatus configured to control the average fill level of an asynchronous first-in-first-out, FIFO, the fill level control apparatus comprising an offset calculation unit adapted to or configured to calculate the offset between a programmable target average fill level and the current average fill level of the FIFO and an adjustment unit adapted to or configured to adjust continuously the empty rate of the FIFO in response to the calculated offset to keep the average fill level of the FIFO constant.

Abstract: A network element is provided that includes a signal interface for receiving satellite signals transmitted by a satellite system and a processing system for producing the timing information based on the satellite signals and on assistance information received from a data transfer network. The network element transmits the timing information to the data transfer network in accordance with a timing transfer protocol. At a start-up, the network element requests a dynamic host configuration protocol server to send host configuration data containing a protocol address to be associated with the network element. The network element reads, from the host configuration data, information enabling the network element to get aware of the assistance information and obtains the assistance information in accordance with the read information. Thus, the dynamic host configuration protocol server enables the network element to operate as a network-assisted source of satellite-based timing.

Abstract: A method for determining the latency or length of an optical path of a fiber-optic transmission link includes: starting a measurement cycle at a first point in time; stopping the measurement cycle at a second point in time after having received a last measurement bit or bit pattern at the first end; determining, at the first end, the total round-trip delay of the optical path by evaluating a time information available at the first end; and calculating the length of the optical path by using the total round-trip delay and the group velocity characterizing the signal propagation along the optical path.

Abstract: There are provided a clock node, a controller, a method of operating the clock node and a method of operating the controller in a time distribution network (TDN) comprising the controller being in data communication with the clock nodes via a control path. The method of operating the clock node comprises: sending, from the clock node via the control path to the controller, a first timestamp-related data; receiving, by the clock node via the control path from the controller, clock-recovery control data generated by the controller using the first timestamp-related data received from the clock node; processing the received clock-recovery control data to extract data usable for phase and frequency recovery; and using the extracted data to steer frequency and phase characterizing the clock node.

Abstract: A method for scheduling a transmission of packets within a network using a common periodic time window, having a congestion protected section, partitioned into time slots, including time slots dedicated to packets being sensitive to a delay variation.

Abstract: A wavelength division multiplexed telecommunication system with automatic compensation of chromatic dispersion in a predetermined wavelength band, said WDM telecommunication system comprising a probe signal detection unit at a receiver side adapted to detect amplitude modulated probe signals generated by a probe signal generation unit at a transmitter side with a predetermined relative phase difference and transmitted through an optical link to said receiver side; and a chromatic dispersion compensation unit adapted to compensate the chromatic dispersion in response to a relative phase difference of the amplitude modulated probe signals detected by said probe signal detection unit at the receiver side.

Abstract: A method for establishing an embedded optical communication channel in an optical WDM transmission system including: creating, at the central network device, a broad-band optical signal, supplying the broadband optical signal, transmitting the broadband optical signal and the plurality of second optical channel signals to an optical demultiplexer device, transmitting an optical signal consisting of a dedicated second optical channel signal and a filtered broadband optical signal; receiving the optical signal and creating a corresponding electrical receive signal and extracting the electrical signal corresponding to the filtered broadband optical signal from the electrical receive signal and detecting whether the electrical signal contains information intended for the respective first channel transceiver.

Abstract: An apparatus for monitoring a performance of an Ethernet data stream, EDS, said apparatus comprising: an evaluation unit adapted to evaluate sync headers and block type fields of line code vectors of the Ethernet data stream, EDS; and a counter unit adapted to increment at least one performance counter in response to the evaluated sync header and the evaluated block type field of each line code vector of the Ethernet data stream, EDS.

Abstract: A redundant optical radiant energy source, especially for metrology applications, including a redundant optical device for creating optical radiation including at least two semiconductor lasers, which are provided on a thermally conducting laser support, at least one thermal sensor configured to detect the temperature of the laser support or at least one of the semiconductor lasers, respectively; and a heating/cooling device thermally connected to or integrally provided with the laser support.

Abstract: A method for creating an optical binary digital transmit signal to be supplied to an optical transmission link including: operating an optical transmitter in such a state that mode hopping occurs between a predefined first and a predefined second optical mode of the optical transmitter if a binary digital modulation signal is supplied to the optical transmitter and creating a modulated optical output signal of the optical transmitter corresponding to the binary digital modulation signal supplied to the optical transmitter. The modulated optical output signal is optically filtered in such a way that at least a portion of the optical power spectrum of the modulated optical output signal caused by a selected one of the first and second optical modes is suppressed or at least substantially attenuated.

Abstract: A method for establishing a self-organized emergency mobile core in a cellular communication network, the cellular communication network having a core element. The method includes the step of storing program code for implementing core network functionality on at least one stationary network element of the cellular communication network allowing to host virtual network functionality. The core network functionality remains inactive when the core element is available. The method includes the steps of detecting an emergency event within the cellular communication network resulting in an unavailability of the core element, and starting operating the core network functionality in order to establish a self-organized emergency mobile core in response to the detected emergency event.

Abstract: A method for establishing bidirectional communication links includes: supplying, to at least two optical transceiver modules at each side of at least two optical paths, a multiplexed optical CW signal comprising at least two optical CW signals having the same differing wavelengths, and modulating the multiplexed optical CW signal according to modulation signals; creating, at each side of the optical paths, at least two first and second optical transmit signals by optically filtering the modulated optical signals so that only a single wavelength remains, and routing pairs of a first and second optical transmit signal to the optical paths, wherein the optical transmit signals of each pair have differing wavelengths and wherein the optical transmit signals transmitted in the same direction over the same optical paths have differing wavelengths; receiving each optical transmit signals at a dedicated optical transceiver module by mixing it with the multiplexed optical CW signal.

Abstract: A method for facilitating participation of an intermediary network device in a security gateway communication including: establishing a secure channel between the intermediary network device and a security gateway; transmitting a virtual machine instantiation command generated by software running in the security gateway to the intermediary network device; instantiating a virtual machine on the intermediary network device; when establishing a secure communication session between the at least one base station and the core network portion via the security gateway for the first time, establishing an Internet Key Exchange communication between the virtual machine and the security gateway and transmitting session keys from the security gateway to the virtual machine during the Internet Key Exchange communication; establishing an IPsec tunnel between the virtual machine and the security gateway.

Abstract: A method for creating an optical transmit signal includes creating an electrical discrete multi-tone signal according to digital input data carrying the information to be transmitted, the discrete multi-tone signal having a plurality of electrical partial signals, each electrical partial signal defining a sub-channel. Each electrical partial signal includes a sub-carrier at a predetermined sub-carrier frequency which is modulated according to a dedicated modulation scheme, so that a dedicated portion of the digital input data is included in each sub-channel. The method includes creating an optical signal by using the electrical discrete multi-tone signal as modulating signal for amplitude-modulating the intensity of an optical carrier signal. The method further includes bandpass-filtering the optical signal in order to create an optical single sideband or vestigial sideband transmit signal.

Abstract: A method for generating a tone signal (TS) having a tone frequency, f, wherein the method comprises the following steps: supplying (S1) a binary bit stream (BBS) having a mark pattern with a supply bit rate, BR, to a signal filter unit; and filtering (S2) the supplied binary bit stream (BBS) by said signal filter unit to generate the tone signal (TS), wherein the mark pattern of the binary bit stream (BBS) supplied to said signal filter unit is adapted to minimize a ratio of the supply bit rate, BR, to the tone frequency, f, of the generated tone signal (TS).

Abstract: An optical connecting system for connecting a first and a second optical device includes a first and a second multi-fiber device connector included in the first and second optical device and a multi-fiber optical connection cable including a plurality of optical fibers and having a first and a second multi-fiber cable connector at a first and second end thereof and being adapted to be connected to the first and second multi-fiber device connector. The optical devices are configured to transmit to and/or receive from the other optical device wanted optical data signals via optical fibers of the multi-optical fiber connection cable.

Abstract: A wavelength division multiplexing, WDM, network comprising an apparatus adapted to manage a frequency spectrum in the wavelength division multiplexing, WDM, network, the apparatus comprising an adjustment unit adapted to adjust a frequency offset between carriers for each individual carrier depending on performance characteristics of the individual carriers.

Abstract: A method for use in connection with a data transmission network includes receiving a plurality of time interval error data samples over a sampling period and comparing a duration of the sampling period to a time threshold for the sampling period. If the duration of the sampling period is less than or equal to the time threshold for the sampling period, the method includes processing the received plurality of data samples so as to calculate in real time a maximum time interval error. However, if the duration of the sampling period exceeds the time threshold for the sampling period, the method includes dividing the sampling period into a finite number of sub-intervals and processing the data samples in each sub-interval so as to produce a respective intermediate result for each sub-interval. Each of these intermediate results is stored directly after it is produced, and these stored intermediate results are processed so as to estimate the maximum time interval error.

Abstract: A chromatic dispersion compensation apparatus for automatic compensation of chromatic dispersion of signals transmitted via an optical link at predetermined wavelengths of WDM channels within a predetermined band. A tapping unit taps optical signals received by the chromatic dispersion compensation apparatus via the optical link at predetermined wavelengths and supply them to an optical coherent receiver adapted to tune its local oscillator to WDM channels to generate corresponding analog electrical signals of the WDM channels which are sampled by an analog digital converter to provide digital signal samples of WDM channels processed by a digital signal processor of the chromatic dispersion compensation apparatus to calculate an estimate residual chromatic dispersion value of the received optical signals.

Abstract: Disclosed is a random light collector device including a reflecting cavity configured to enclose a random light source that randomly transmits photons. The reflecting cavity has an inner wall adapted to reflect at least a portion of the photons to an output port and guiding means for directing the photons to a photodetector. The guiding means is a hollow tube having an inner wall adapted to reflect the photons, wherein a first end of the hollow tube is connected to or positioned adjacent to the output port of the reflecting cavity and wherein the photodetector is provided within the hollow tube or at a second end such that a sensitive area of the photodetector covers the cross-section of the second end.