Abstract: A transmission and reception apparatus, includes a processor and a processing device coupled to the processor, wherein the processor is configured to detect insertion of a pluggable module, issue, when the insertion of the pluggable module is detected, an instruction to the processing device to generate a first test signal to be supplied to the pluggable module, extract an alternating current component from a first monitoring result of the first test signal by the pluggable module and acquiring pulse width information at a plurality of phase points, and set a phase point determined based on the pulse width information as an optimum phase value to the processing device.

Abstract: There is provided an optical transmission device including a light source configured to generate light used for coherent detection processing of reception light; a monitor configured to monitor a frequency offset between the reception light having a plurality of protection wavelengths and the light generated by the light source, based on a signal obtained by the coherent detection processing of the reception light having the plurality of protection wavelengths available for a work wavelength by the light generated by the light source; and a controller configured to select a protection wavelength to be switched to the work wavelength among the plurality of protection wavelengths, based on the frequency offset monitored by the monitor.

Abstract: There is provided an optical transmission device including a light source configured to generate light used for coherent detection processing of reception light; a monitor configured to monitor a frequency offset between the reception light having a plurality of protection wavelengths and the light generated by the light source, based on a signal obtained by the coherent detection processing of the reception light having the plurality of protection wavelengths available for a work wavelength by the light generated by the light source; and a controller configured to select a protection wavelength to be switched to the work wavelength among the plurality of protection wavelengths, based on the frequency offset monitored by the monitor.

Abstract: A transmission apparatus includes: a frame transmitter configured to receive an asynchronous first frame transmitted via a first transmission network and arrange the received first frame to a second frame to transmit the arranged second frame to a second transmission network; a congestion detector configured to detect congestion that has occurred in an asynchronous transmission apparatus that receives the first frame via the first transmission network; and a band controller configured to control a transmission band of a path so as to reduce the transmission band of a path on the second transmission network corresponding to a path on which the congestion has occurred.

Abstract: A transmission apparatus includes: a backboard configured to be interposed between a detachable first unit and a detachable second unit, wherein the backboard includes: an electrical connector coupled to the first unit; an optical modulation unit configured to modulate light from a light source based on a first electrical signal from the first unit via the electrical connector and output a first optical signal; and a first optical transmission path configured to transmit the first optical signal to the second unit.

Abstract: In an apparatus for accommodating and multiplexing asynchronous client signals in which an idle signal is defined, the transmission side transmits client signals after synchronizing the client signals by inserting or removing, with reference to a specific client signal, an idle signal to/from the same type of another client signal, and in the receiving side, a PLL part is shared by recovering a clock from a client signal and distributing the clock for another client signal.

Abstract: A communication device includes a frame processing unit configured to allocate a plurality of first regions and a plurality of second regions in a frame, and contain portions of a packet in the plurality of first regions, a transmitting unit configured to transmit the frame, and a receiving unit configured to receive a retransmission request for the packet, wherein the frame processing unit contains a retransmission data packet in at least one of the plurality of second regions in accordance with the retransmission request received by the receiving unit.

Abstract: A transmission apparatus includes: a frame transmitter configured to receive an asynchronous first frame transmitted via a first transmission network and arrange the received first frame to a second frame to transmit the arranged second frame to a second transmission network; a congestion detector configured to detect congestion that has occurred in an asynchronous transmission apparatus that receives the first frame via the first transmission network; and a band controller configured to control a transmission band of a path so as to reduce the transmission band of a path on the second transmission network corresponding to a path on which the congestion has occurred.

Abstract: In a destuff circuit, after invalid data included in each data signal assigned to a plurality of lanes in a stuff shifter is collected to one side within the same column, then in a data rotator the number of stuffs of the respective data signals of each column is detected, and the data of the respective columns are operated to rotate in one direction, according to the detection results. Then, effective data included in the data signal of each lane that has been rotated is stored in FIFO, to thereby output signals for which ineffective data has been removed and only effective data has been extracted. As a result, it becomes possible to perform destuffing processing for parallel data signals with simple logical circuits at high speed.

Abstract: In an apparatus for accommodating and multiplexing asynchronous client signals in which an idle signal is defined, the transmission side transmits client signals after synchronizing the client signals by inserting or removing, with reference to a specific client signal, an idle signal to/from the same type of another client signal, and in the receiving side, a PLL part is shared by recovering a clock from a client signal and distributing the clock for another client signal.

Abstract: There is provided a transmission apparatus including a receiver unit configured to receive, from a network on a first layer, fault information regarding the network on the first layer, and a generator unit configured to generate, based on the fault information received by the receiver unit, switch information used to switch a transmission path of a network on a second layer higher than the first layer.

Abstract: A redundancy control method is disclosed that controls a first redundancy function that switches between a working line and a protection line in response to a detection of a line error and a second redundancy function that performs a path switching in response to a detection of a path error in a ring network operating at a path rate lower than a line rate thereof. The method comprises a step of masking the path error detection within a period from a time of the detection of the line error to an expected time of the detection of the path error.

Abstract: In a destuff circuit, after invalid data included in each data signal assigned to a plurality of lanes in a stuff shifter is collected to one side within the same column, then in a data rotator the number of stuffs of the respective data signals of each column is detected, and the data of the respective columns are operated to rotate in one direction, according to the detection results. Then, effective data included in the data signal of each lane that has been rotated is stored in FIFO, to thereby output signals for which ineffective data has been removed and only effective data has been extracted. As a result, it becomes possible to perform destuffing processing for parallel data signals with simple logical circuits at high speed.

Abstract: In a path status monitoring method and device which can enhance or reduce a band more rapidly, for example, SONET frames FR serially connected over 32 frames to which frame Nos. FN (“0”-“31”)) are assigned are cyclically generated respectively for paths P0-P2 in a cycle TC (=64 ms). After output timing delays TD0-TD2 of the frames FR are shifted by an optimal delay interval D (=21 ms) between the paths P0-P2 based on the number of the paths “3”, the output timing delays TD1 and TD2 are restored by preliminarily obtained transmission delays for the paths P1 and P2 to the path P0. When the frames FR are transmitted through each of the paths P0-P2, statuses (path statuses MST) where a reception fault has occurred in each of the paths P0-P2 are collected to be stored in the frame whose frame No. FN=“0”.

Abstract: The present invention discloses a method for controlling a physical bandwidth of a ring-based network by employing a ring application of a data link layer that operates in a physical layer. The method includes the steps of a) requesting each of a plurality of node apparatuses included in the ring-based network to confirm whether the bandwidth can be changed, b) instructing each node of the apparatuses to prepare for the bandwidth change upon receiving a confirmation that the bandwidth can be changed, c) reporting that the preparation for the bandwidth change is completed, and d) changing the bandwidth by using a bandwidth changing function of the ring application upon receiving the report of the completion of the preparation for the bandwidth change.

Abstract: There is provided a transmission apparatus being operable to realize a link capacity adjustment scheme (LCAS) between a plurality of nodes forming a network over which signals are transmitted by using a virtual concatenation (VCAT) system, the transmission apparatus including a receiving part being operable to detect a failure of a member as a transmission path forming a virtual concatenation group (VCG) in each member, and a controller being operable to control setting of detection conditions of the failure received at the receiving part in each member.

Abstract: A signal distribution method and a signal distribution apparatus are disclosed, wherein transport packets of a television signal containing multiplexed channels are provided in a transmission format of a digital broadcasting standard, and such transport packets are transmitted and distributed over a synchronous network. Transmission rate (data speed) of the transport packets of a given customer in the synchronous network is selectable based on the number of multiplexed channels for the customer.

Abstract: When an externally received data frame is transmitted at a station of a ring-shaped packet communication network, a congestion point in the communication network is defined as a boundary point, a frame addressed to a station located before the boundary point is transmitted at a first transfer rate, and a frame addressed to a station located after the boundary point is transmitted at a second transfer rate lower than the first transfer rate.

Abstract: It is aimed at providing a brazing flux powder, which exhibits an excellent spreadability in case of brazing of an Mg-containing aluminum-based material, which is non-corrosive and is thus excellent in safety, which is relatively inexpensive and is thus economically excellent, and which can be used in a wide and general manner. There is provided an improvement in a flux powder containing therein KAlF4, K2AlF5, and K2AlF5·H2O, usable for brazing of an aluminum-based material having an Mg content of 0.1 to 1.0 wt %, and the improving characteristic configuration resides in that the flux powder has a composition where a K/Al molar ratio is within a range of 1.00 to 1.20 and an F/Al molar ratio is within a range of 3.80 to 4.10, and the K2AlF5 and K2AlF5·H2O have a sum content of 6.0 to 40.0 wt %, balance KAlF4, and that part or the whole of the crystal structure of K2AlF5·H2O is at least one of a K-defective type, F-defective type, and K-and-F-defective type crystal structure.

Abstract: In a path status monitoring method and device which can enhance or reduce a band more rapidly, for example, SONET frames FR serially connected over 32 frames to which frame Nos. FN (“0”-“31”)) are assigned are cyclically generated respectively for paths P0-P2 in a cycle TC (=64 ms). After output timing delays TD0-TD2 of the frames FR are shifted by an optimal delay interval D (=21 ms) between the paths P0-P2 based on the number of the paths “3”, the output timing delays TD1 and TD2 are restored by preliminarily obtained transmission delays for the paths P1 and P2 to the path P0. When the frames FR are transmitted through each of the paths P0-P2, statuses (path statuses MST) where a reception fault has occurred in each of the paths P0-P2 are collected to be stored in the frame whose frame No. FN=“0”.