Abstract: A shaping apparatus comprising a plurality of buffer memories allocated for different flows, bandwidth control units associated with the buffer memories, and a read control unit, wherein each of the bandwidth control units issues a first frame output request based on a maximum allowed bandwidth and a second frame output request based on a minimum guaranteed bandwidth, and the read control unit selects a bandwidth control unit to be permitted for frame output execution out of bandwidth control units that are issuing the first or second frame output request, giving priority to the second frame output request.

Abstract: A multiplex conversion unit is configured with those functions required for a specific network to which it is more economically applicable. Each OC-12IF circuit pack includes a switch for performing time slot assignment (TSA) between a plurality of high-speed transmission lines and at least a low-speed transmission line. An ADM circuit pack includes a switch for performing time slot interchange (TSI) between the high-speed transmission lines and the low-speed transmission line. In an application to a network requiring the TSI function, the switch of the OC-12IF circuit pack performs only the add/drop multiplex (ADM) operation between the signals input/output by the high-speed transmission lines and the ADM circuit pack, and the switch on the ADM circuit pack performs the TSI operation. In an application not requiring the TSI, the TSA operation is performed using a THRU circuit pack.

Abstract: An ATM network for synchronously perform a path connection control at a plurality of nodes, wherein path control data are preliminarily supplied to the nodes from a network management system before a designated operation time. Each node generates a current time synchronously with a network synchronous clock, selects path control data by comparing the designated operation time of the control data with the current time, and autonomously executes a path connection control in accordance with the selected path control data.

Abstract: An ATM communication apparatus having a buffer memory 11 for storing cells received from each of input lines, a write control unit 13 for writing each of the received cells into the buffer memory so that the cells stored in the buffer memory form cell queues corresponding to connections for each output line, a read control unit 17 for reading out cells from each of the cell queues while guaranteeing a minimum cell rate predetermined for each connection within a range not exceeding a predetermined peak cell rate, and a unit 12 for adding congestion indication to a cell read out from a cell queue of which stored cell amount exceeds a preset threshold.

Abstract: An optical transmission system accomplishes optical transmission to a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission to a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-toelectric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, an with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: An optical transmission system accomplishes optical transmission to a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission to a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-to-electric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, an with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: An optical transmission system accomplishes optical transmission to a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission to a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-to-electric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, an with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: Disclosed are the ATM communication apparatus and the bandwidth control method thereof that are capable of bandwidth control to guarantee the minimum cell rate and limit the upper-limit for each of subscriber terminals, dynamically and fairly distribute the shared bandwidth based on the register status and can be easily applied to the system that is already operating the actual service.

Abstract: An optical transmission system accomplishes optical transmission over a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission over a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-to-electric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, and with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: A uni-direction protection switched ring node which switches from a working path to a protection path or vice versa includes a failure-information detect circuit which detects a failure occurring on the working path and a failure occurring on the protection path independently of each other as failure information. A failure-information-path identifying circuit determines whether a working path with a failure occurring thereon is an active or standby path or determines whether a protection path with a failure occurring thereon is an active or standby path. A select circuit selects either the working or protection path as an active path in accordance with results of detection and determination by the failure-information detect circuit and the failure-information-path identifying circuit respectively.

Abstract: An ATM switch including ECC encoder circuits each for generating, for an ATM cell as an information symbol, an ECC check symbol and for adding the ECC check symbol thereto, cell partitioning circuits each for subdividing an information field of an ATM cell into N partial cells, for subdividing a check symbol field into M partial cells, and for assigning an identical routing tag to the obtained partial cells (N+M) partial cell switches for respectively routing the (N+M) partial cells in an independent fashion based on the routing tag, and ECC decoder circuits for receiving the (N+M) partial cells thus routed and for achieving an error correction on the received partial cells.

Abstract: An alarm detect unit (a path switching apparatus) for selecting an active path comprises a path-alarm detect circuit and a guard timer for a working path as well as a path-alarm detect circuit and a guard timer for a protection path. When an alarm is detected on the active path, alarm information, that is, information on the generation of the alarm, is delayed by a predetermined time by the guard timer of the working or protection path that serves as the active path.By the same token, when an alarm is detected on a standby path, alarm information, that is, information on the recovery of the alarm, is delayed by a predetermined time by the guard timer of the working or protection path that serves as the standby path. Either the working or protection path is then selected as the active path in accordance with pieces of alarm information output by the two guard timers which indicate the line-failure-occurrence states of the active and standby paths.

Abstract: An optical transmission system accomplishes optical transmission over a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission over a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-toelectric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, and with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: An optical transmission system accomplishes optical transmission to a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission to a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-to-electric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, an with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: An ATM switch including ECC encoder circuits each for generating, for an ATM cell as an information symbol, an ECC check symbol and for adding the ECC check symbol thereto, cell partitioning circuits each for subdividing an information field of an ATM cell into N partial cells, for subdividing a check symbol field into M partial cells, and for assigning an identical routing tag to the obtained partial cells (N+M) partial cell switches for respectively routing the (N+M) partial cells in an independent fashion based on the routing tag, and ECC decoder circuits for receiving the (N+M) partial cells thus routed and for achieving an error correction on the received partial cells.

Abstract: A multiplex conversion unit is configured with the functions required for a specific network to which it is applicable more economically. Each OC-12IF circuit pack includes a switch for performing time slot assignment (TSA) between a plurality of high-speed transmission lines accommodated in the OC-12IF circuit pack and at least a low-speed transmission line accommodated in at least a DS3IF circuit pack. An ADM circuit pack includes a switch for performing time slot interchange (TSI) between the high-speed transmission lines and the low-speed transmission line. In an application to a network requiring the TSI function, the switch of the OC-12IF circuit pack performs only the add/drop multiplex (ADM) operation between the signals input/output by the high-speed transmission lines and the ADM circuit pack, and the switch on the ADM circuit pack performs the TSI operation.

Abstract: An optical transmission system accomplishes optical transmission to a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission to a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-to electric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, and with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: An optical transmission system accomplishes optical transmission to a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission to a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-toelectric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, an with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.

Abstract: An ATM switch including ECC encoder circuits each for generating, for an ATM cell as an information symbol, an ECC check symbol and for adding the ECC check symbol thereto, cell partitioning circuits each for subdividing an information field of an ATM cell into N partial cells, for subdividing a check symbol field into M partial cells, and for assigning an identical routing tag to the obtained partial cells (N+M) partial cell switches for respectively routing the (N+M) partial cells in an independent fashion based on the routing tag, and ECC decoder circuits for receiving the (N+M) partial cells thus routed and for achieving an error correction on the received partial cells.

Abstract: A self-healing ring switch transmission system uses space division switches disposed upstream and downstream of an add drop switch in order to determine a correspondence with a plurality of ring-switch modes by merely changing the software. This is accomplished by having one output highway of the add drop switch and one output highway of a space division switch connected with an input stage of a selector for selecting one time slot of the two output highways.