Fujitsu Corporation

Susumu Eda

Kenji Tanaka

Osamu Sekihata

Ryuji Hyodo

Hiroyuki Hatta

Katsumi Oomuro

Reiko Norizuki

Tetsuo Nishino

Reiko Furuya

Akihiro Okada

Eisuke Iwabuchi

Nakaba Yuhara

Toru Kino

Hirokazu Minou

Shuichi Naito

Katsumi Oomura

An information delivery system includes terminals receiving data via a satellite-communication system, and a user center having a destination-conversion table which lists a satellite-system receiver ID with respect to each ground-network address of the terminals, and, upon receiving a request for data delivery via an intra-network, obtaining satellite-system receiver IDs from ground-network addresses indicated as destinations of the data delivery by referring to the destination-conversion table so as to deliver requested data and a reception-control program to the destinations via the satellite-communication system. The terminals use the reception-control program to check the data-reception conditions when receiving the requested data and the reception-control program, and send a request for a repeat of the data delivery to the user center via the intra-network if the data-reception conditions are not satisfactory.

Information delivery system using satellite communication

An ATM multiplex transmission system including AAL processing units, an ATM cross connection processing unit, and a plurality of lines connected to the same, wherein the system has test equipment formed in it, the test equipment being formed as a particular cell generating unit and a routing information setting unit in at least one of the line corresponding points which the ATM cross connection processing unit has at the portions connecting with the lines. When a routing test is performed in the system, the VPI and the VCI designating the route are given from the outside as the routing information.

ATM multiplex transmission system having test equipment

In a congestion control system for an interface between a PBX and an ATM multiplexing transmission unit connected to a network via an ATM transmission line, a congestion detecting unit detects a congested state in which the ATM transmission line is congested with traffic. A control unit inhibits a call from the PBX from being sent to the ATM transmission line via the ATM multiplexing transmission unit when the congestion detecting unit detects the congested state.

System and method for controlling interface between PBX and ATM

An ATM multiplex transmission system including an ATM adaptation layer (AAL) processing unit, an ATM cross connection processing unit having a switch and FIFO memories connected to the incoming and outgoing sides, and dummy load cell generating units which forcibly write dummy load cells in the incoming FIFO memories or outgoing FIFO memories, the writing of the dummy load cells being used to execute a load test on the FIFO memories.

A method for supervising and controlling ATM traffic, which uses idle cells transferring traffic information to manage a network, comprising steps of a first step for mapping traffic information in the information field of an idle cell and transferring said idle cell to other communication nodes, a second step for performing the operation of traffic control in accordance with the contents of said traffic information included in said idle cell on the receiving side of said other communication nodes, and a third step for assembling a new idle cell including said traffic information of received idle cell and/or new traffic information on said receiving side of communication nodes and transferring said new idle cell from said receiving side of communication nodes to other communication nodes.

Apparatus and a method for supervising and controlling ATM traffic

An apparatus for supervising and controlling ATM traffic, and which collects traffic information, including a cell detecting unit for outputting a cell detecting signal whenever detecting a user information cell flowing through an ATM switch unit, an idle cell detecting unit for outputting an idle cell detecting signal whenever detecting an idle cell flowing through an ATM switch unit, a cell counting unit for counting the cell detecting signals output from the cell detecting unit, an idle cell counting unit for counting the idle cell detecting signals output from the idle cell detecting unit, an idle cell rate detecting unit for detecting an idle cell rate from both counts output from the cell counting unit and the idle cell counting unit at regular intervals, and a control unit for performing the operation of traffic control in accordance with the idle cell rate provided from the idle cell rate detecting unit at regular intervals.

In an ATM cell assembling and disassembling method for a communications network having first and second communications nodes, HDLC data is transferred from a first terminal to the first communications node via a first transmission line, the HDLC data conforming to an HDLC format. It starts to assemble, in the first communications node, at least one cell from the HDLC data when data which is contained in the HDLC data and equal to one cell has been received. Then the above at least one cell of ATM data is transferred from the first communications node to the second communications node. Disassembly is started, in the second communications node, of the above at least one cell of ATM data to thereby generate original HDLC data when a fluctuation compensation time has elapsed after a first cell of ATM data among the above-mentioned at least one cell of ATM data is received by the second communications node. The fluctuation compensation time is based on a maximum fluctuation time of a route connecting the first and second communications nodes to each other as well as a bit rate of the first transmission line. Finally, the original HDLC data is transferred to a second terminal from the second communications node via a second transmission line.

ATM cell assembling and disassembling system and method

An apparatus for setting a communication path in ATM communication, comprises: communication path control unit for indicating a communication path test before starting communication; test cell assembling unit for assembling test cells that consist of a series of cells each of which has a sequential number for detecting test cell discard and has the higher cell discard priority (CLP=1); communication path setting unit for setting up the communication path and replacing transmit idle cells with the test cells; and cell-discard detecting unit for comparing the sequential number contained in received test cells with the number of the received test cells and thereby outputting a communication path setting enable or disable control signal.

Apparatus and a method for setting a communication path

An apparatus for supervising and controlling ATM traffic, and which collects traffic information, comprises a cell detecting unit for outputting a cell detecting signal whenever detecting a user information cell flowing through an ATM switch unit, an idle cell detecting unit for outputting an idle cell detecting signal whenever detecting an idle cell flowing through an ATM switch unit, a cell counting unit for counting the cell detecting signals output from the cell detecting unit, an idle cell counting unit for counting the idle cell detecting signals output from the idle cell detecting unit, an idle cell rate detecting unit for detecting an idle cell rate from both counts output from the cell counting unit and the idle cell counting unit at regular intervals, and a control unit for performing the operation of traffic control in accordance with the idle cell rate provided from the idle cell rate detecting unit at regular intervals.

A fault notifying system notifies a fault in an asynchronous transfer mode (ATM) network to at least one data terminating equipment (DTE). The fault notifying system includes a network interface coupled to the ATM network for outputting an alarm indication signal (AIS) when a fault is generated in the ATM network. An ATM crossconnect part generates an AIS cell having a predetermined signal format in response to the AIS. An adaptation layer processing part forms ATM cells, disassembles ATM cells and outputs a data circuit-terminating equipment not ready (DNR) in response to the AIS cell. A terminal interface coupled to the DTE notifies the fault in the ATM network to the DTE in response to the DNR. The AIS cell has a cell format identical to an ATM cell format but has predetermined information in a specific part of the ATM cell format to distinguish the AIS cell from the ATM cell.

Fault notifying system for asynchronous transfer mode communication

In a VPI and VCI assignment system in an ATM system having a plurality of nodes and terminals, each of the nodes including a conversion unit which generates ATM cells from data sent from one of the terminals, and a node management unit which manages a corresponding one of the nodes, a management unit assigns VPIs and VCIs to calls and manages information concerning VPIs and VCIs currently assigned to the calls and idle VPIs and VCIs. An assignment requesting unit, which is provided in each of the nodes and connected to the management unit, requests the management unit to assign a VPI and a VCI to a call received from one of the terminals. An assignment cancelling unit, which is provided in each of the nodes and connected to the management unit, requests the management unit to cancel the VPI and VCI assigned to the call in response to an end of a communication related to the call.

VPI and VCI assignment system in ATM system

An ATM exchange system includes a unit for detecting management cells from among multiplexed input ATM cells, and a path creating unit dedicated to the detected management cell. The path creating unit is activated each time the management cell detecting unit detects the management cell, and thus the management cell is transferred to the corresponding outgoing line without loss in the exchange, and can be transferred thereto before a user ATM cell.

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Kawasaki, Japan

Susumu Eda