Abstract: A monitoring apparatus for detecting uncharacteristic short-term power level changes of an optical signal transmitted through an optical fiber, said monitoring apparatus comprising a power level variance calculation unit adapted to calculate a power level variance on the basis of a long-term power level and a current power level of said optical signal and a short-term variance filter adapted to filter transient changes indicated by the calculated power level variance and to generate a trouble occurrence indication indicating an uncharacteristic short-term power level change, if the filtered power level variance exceeds a predetermined power level variance.

Abstract: A network comprising a latency monitoring point adapted to calculate a forward latency of a path between a master node and a slave node on the basis of time stamps which are exchanged periodically between said master node and said slave node by a time alignment protocol used in said network.

Abstract: A method is described for accessing a virtual private network over a packet switched network. The method includes the steps of sending, by a provider edge router, network labeling information about data packet labels to a network access device using a layer 2 network protocol.

Abstract: The invention relates to a method of cooling electronic circuit boards using surface mounted devices (SMD), the method comprising the steps of: after or during the board layout, filling empty spaces V1, V2, V3, V4, V5, V6, V7, V8, V9, V10 with at a number of heat sink devices 1, 2, 3, 4, 5 near a thermal hot spot and connecting the number of heat sink devices 1, 2, 3, 4, 5 to a thermally conducting path 25, 27, 29, 31, 33, 35 of the board N, respectively. Further, the invention relates to a heat sink device 1, 2, 3, 4, 5 adapted to implement the method according to the invention.

Abstract: A method and apparatus for suppressing pump-mode optical beat interference noise in a Raman amplified fiber link of an optical network, wherein a wavelength of a laser beam generated by a first pump laser and a wavelength of a laser beam generated by a second pump laser of a pair of polarization multiplexed pump lasers are detuned with respect to each other to suppress the optical beat interference, OBI, noise in the Raman amplified fiber link of said optical network.

Abstract: The subject matter described herein is directed to an apparatus and a method for reduction of bit errors in continuous data transmission via a data transmission medium, the apparatus having a monitoring unit for monitoring of transceiver parameters of at least one transceiver transmitting said data and/or medium parameters of said data transmission medium and a calculation unit for predicting a time and a duration of an occurrence of at least one event affecting a bit error rate of said continuous data transmission depending on the monitored parameter; and a control unit for throttling a bandwidth of a data switch connected to said transceiver during the predicted duration of the event for bit error reduction.

Abstract: The invention pertains to a mobile terminal for servicing a telecommunication system, wherein the telecommunication system comprises a system controller and at least one module and/or at least one interface port (that is externally accessible in the inserted state of the module), wherein the mobile terminal features an identification device in order to identify a module or an interface port. The invention further pertains to a utilization of such a mobile terminal, as well as an arrangement consisting of a telecommunication system and such a mobile terminal.

Abstract: The invention relates to a network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage for receiving a pluggable module which performs a traffic management of data transported via at least one optical fiber connected to said pluggable module.

Abstract: A method and apparatus for performing an automatic power adjustment wherein a signal power level of an optical signal transmitted by an optical transceiver via an s optical span to a far-end device is adjusted automatically in response to a determined span loss of the optical span to achieve a predetermined desired receive signal power level of the optical signal at the far-end device.

Abstract: A method and apparatus for performing an automatic power adjustment wherein a signal power level of an optical signal transmitted by an optical transceiver via an optical span to a far-end device is adjusted automatically in response to a determined span loss of the optical span to achieve a predetermined desired receive signal power level of the optical signal at the far-end device.

Abstract: The invention relates to a method of operating a primary optical node, particularly an optical line terminal (OLT), for an optical communications system, wherein said OLT is configured to receive at least one upstream optical signal (uos) from at least one secondary optical node, particularly an optical networking unit (ONU), within at least a first wavelength range (wr1), and to transmit at least one downstream optical signal (dos) to said at least one ONU within at least a second wavelength range (wr2), wherein said OLT determines a currently unused wavelength subrange (wsr2) within said first wavelength range (wr1), assigns a specific target wavelength (?t) within said currently unused wavelength subrange (wsr2) to said ONU, signals said target wavelength (?t) to said ONU, receives an upstream signal (us) from said ONU, and provides feedback information to said ONU.

Abstract: The invention relates to a network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage, for receiving a pluggable module which performs signal processing of data comprised of at least one WDM channel transported via at least one optical fiber connected to said pluggable module in the optical domain.

Abstract: The invention relates to a filter system for cleaning the air of an enclosure to be ventilated, especially for fiber-optic equipment. The enclosure includes a ventilation opening and is associated with an insertion shaft located proximate to the ventilation opening. The filter system includes an insertion part including a filter housing for accommodating at least one filter element and further including a handle for inserting the insertion part into the insertion shaft. The filter housing is configured so as to cover the ventilation opening when the filter housing is in a working position within the insertion shaft. The filter system includes an insertion arrangement provided at a first end portion of the insertion shaft for inserting the insertion part into the insertion shaft.

Abstract: The invention provides a dual polarization transceiver (1) being switchable between two operation modes, wherein in a first operation mode an optical QAM—(Quadratur Amplitude Modulation) signal having a predetermined number (M) of constellation points is generated by said dual polarization transceiver (1) and wherein in a second operation mode an optical QPR—(Quadratur Partial Response) Signal having a predetermined number (L) of constellation points is generated by said dual polarization transceiver (1).

Abstract: An optical transmission system method including generating for a tunable laser a pilot tone having an adjustable pilot tone frequency identifying a wavelength division multiplexing channel used by the tunable laser; multiplying the pilot tone with pilot tone data to provide a pilot tone data signal; supplying the pilot tone data signal and a high frequency data signal to the tunable laser generating an optical laser signal output by the tunable laser responsive to the supplied signals; transporting the optical laser signal to a central wavelength to locker; converting the received optical laser signal to provide a pilot tone data signal for wavelength division multiplexing channels demodulated to detect the pilot tone and the pilot tone data for each individual wavelength division multiplexing channel; and identifying the wavelength division multiplexing channel on the basis of the pilot tone frequency of the detected pilot tone and evaluating the pilot tone data.

Abstract: In one aspect, the present invention embraces a wavelength locking method for causing a narrow-band wavelength spectrum of an optical transmit signal of an optical transceiver device to track a narrow-band wavelength spectrum of an optical receive signal received by the optical transceiver device Further, the present invention embraces a wavelength lockable optical transceiver device, especially for a passive optical transmission network, using this wavelength locking method.

Abstract: A method and an apparatus for providing a flexible secondary data path control, said method comprising the steps of: detecting (S1) a primary data path failure of a primary data path between a customer premise site (3) and a central office site (4); initiating (S2) a corresponding secondary data path if a primary data path failure of said primary data path has been detected; initiating (S3) a measurement of data path characteristics of said initiated secondary path or utilizing constantly monitored data path characteristics of paths for an available secondary data path; and determining (S4) services to be provided via said secondary data path depending on the measured data path characteristics of said secondary data path.

Abstract: A network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage for receiving a pluggable module wherein the pluggable module comprises Time Division Multiplexing (TDM) between an optical network interface and an electrical host interface.

Abstract: A data transport card comprising an interface to receive high speed data streams from at least one client, and a pluggable conversion module which converts said data streams into optical data signals and couples these optical data signals into at least one wavelength division multiplexing channel for transport of said optical data signals via an optical fiber.

Abstract: The invention provides a network and a method for bidirectional transport of data and in particular a pluggable module for bidirectional transport of data via at least one optical fiber between host devices providing an add/drop functionality by means of an integrated bandwidth adaption unit. The network comprises at least one host device having an interface card connected to a backplane of the host device, wherein the interface card comprises at least one cage for receiving a pluggable module which provides the add/drop functionality between an optical interface and the electrical host interface.