Fujitsu Corporation

Fujitus Limited

Sumie Morita

Takashi Hatano

Ryouzi Takano

Shigeru Sekine

Kiyohumi Mitsuze

Yoshihiro Watanabe

Kenichi Okabe

Eiji Ishioka

Hisashi Koga

Hiromi Odaka

Tsutomu Shiomitsu

Yoshiharu Kato

Satoshi Kakuma

Takashi Nara

Katsuaki Akama

Yuzo Okuyama

Hiroshi Nishida

Emi Hata

Megumi Shibata

Hiroyuki Sasai

Masataka Sakai

Noboru Ise

Kenji Kazehaya

Hiroyoshi Yoda

Hitoshi Ouchi

Tomoki Someya

Toshiaki Oishi

Ryouji Takano

Masako Shinmura

Yuzou Kawamura

Miho Tsuchiya

Emi Nemoto

A message division communication method and system are disclosed for a communication system comprising a host, an intermediate device connected to the host through a high-speed bus and a remote device connected to the intermediate device or the host through a low-speed bus. A message is transmitted in such a manner that the host designates and notifies the remote device of a maximum message length determined in a way corresponding to the transmission rate of the low-speed bus and divides the message into division messages each not exceeding the maximum message length thereby to transmit and receive the division messages between the host and the remote device. Even with a communication system in which low-speed and high-speed buses coexist, a message can be transmitted and received by a common communication control scheme.

Message division communication method and communication system

A communication signal suppressing apparatus capable of reducing a load of a firmware using portion is provided in a communication signal apparatus such as a common line signal apparatus. A common line signal processing circuit corresponds to hardware used to execute a portion of the level-2 process operation, and this common line signal processing circuit owns such a function capable of discarding a reception frame having no meaning other than a confirmation response, and also capable of extracting a reverse-direction sequence number thereof. As a result, the common line signal processing circuit performs a remaining level-2 process operation. Thus, since a workload of a processing apparatus (CPU) using the firmware can be reduced, this firmware can be designed with sufficient capacities. Also, other process operations can be carried out by this CPU.

Communication signal suppressing apparatus and common line signal apparatus capable of reducing workload of firmware

An RS,C driver inside target firmware controls an RS,C interface. An OS debugger steals an input to and an output from another function block that is the actual target firmware, and exchanges that input and output with the RS,C driver,. This configuration makes it possible to easily connect a device that executes the target firmware to, for example, a personal computer, using a general purpose RS,C interface, and makes it possible to easily obtain debugging operation using the PC side debugger.

Debugging and cosimulation method for wide band switch firmware

In a path audit control method, (1) a unit (a discrete unit or common unit) within a switch holds bitmap information indicating whether each channel identifier is being used to establish a path; (2) a central controller sends the unit bitmap information indicating whether each channel identifier has been used to establish a path; (3) the unit compares bitmap information which it itself is holding with bitmap information that has been sent from the central controller; and (4) if the bitmap information held by the unit and the bitmap information that has been sent from the central controller do not match, the central controller and the unit cooperate to execute matching processing in such a manner that the compared items of bitmap information will be made to match.

Method of controlling path audit in switches

An ATM exchange system which handles fixed-length cells, such as an ATM exchange, is designed in such a manner that even when a failure occurs particularly in an interface unit or an ATM switch section, downstream stations can be informed of the failure reliably and that when some failure is detected, counting of a charge counter is disabled to always ensure proper charging. For a method of matching between software and hardware in the ATM exchange system including the ATM switch section having a plurality of line associated sections and firmwares associated with those line associated sections, and a call control processor for controlling the ATM switch section, identifiers of an SVC (Switched Virtual Channel) call and a PVC (Permanent Virtual Channel) call are given to connection information of software on the call control processor, connection data affixed with the identifier of the SVC call is released only on the software on the call control processor during a restarting process of the call control processor, and a request to release the SVC call to all the line associated sections in the hardware of the ATM switch section, whereby matching of path information between the software on the call control processor and the hardware of the ATM switch section is performed.

Method for attending occurrence of failure in an exchange system that exchanges cells having fixed-length, and interface unit and concentrator equipped in the exchange system using the method

An ATM (asynchronous transfer mode) switching system is capable of performing a charging process, while suppressing a data communication amount used to acquire data required for a charging process. The ATM switching system is arranged by comprising: a charging data processing unit for counting a quantity of transmitted ATM cells with respect to each of transmission destinations, and for notifying the count value as charging data; a charging information processing unit for requesting the charging data processing unit to notify the charging data, and for notifying charging information produced based on the charging data; and a control unit for requesting the charging information processing unit to notify the charging information.

ATM switching system

A central control unit responsible for path control collects data from a distribution/concentration unit by issuing thereto a command containing the specification of multiple data items. The command also contains the specification of a window size. Of the requested data, the distribution/concentration unit first transmits data in an amount not exceeding the window size, and then, after reception of an ACK order from the central control unit, transmits remaining data if any.

Method of collecting large amounts of data in apparatus such as ATM

An ATM switch system performs a DMA (direct memory access) transfer of a command and status data between a call processor and a processor of a communications control device via a peripheral interface. An inter-processor DMA transfer controller of the communications control device controls a DMA transfer between its memory and the main memory of a call processor for expediting communications between the two processors.

Communications control system for transferring commands/status data in

A subscriber line control device utilizes a scan input table and a last look table. The scan input table stores respective current line states of a plurality of analog subscriber lines. The last look table stores respective preceding line states of the plurality of analog subscriber lines and information for validating or invalidating a timer device. A valid timer device corresponds to when a monitoring process is required. The scan input table is compared with the last look table at every predetermined cycle. When they do not match, it is judged whether the line state has changed or if the timer device is validated. Based on the judging result, an analog subscriber line control is performed according to an instruction specified by a call processing unit. The analog subscriber control is any of a call origination monitor, a dial pulse monitor, and an on-hook and off-hook (HIT) monitor.

Subscriber line control apparatus to concurrently detect change in line

The present invention relates to a system for controlling a miscellaneous device such as a remote device associated with an exchange which handles a fixed length cell with a control field and an information field. The object of the invention is to offer a system where an exchange can control a miscellaneous device such as a remote device in accordance with the feature of the exchange. The exchange includes a call processor, a switch and a signal device. In order to control the miscellaneous device, a path is formed between the signal device and the miscellaneous device. Control information from the call processor is cellulated. The path notifies the miscellaneous device of the control information including cell via the switch to control the miscellaneous device by the exchange.

System of controlling miscellaneous means associated with exchange

A packet data switching system having packet switching equipment and a plurality of transfer control units cooperating with the packet switching equipment exchanging packet data to be transferred through the transfer control units. In the system each packet data is divided into packet frames each having the same frame length and all the packet frames are processed synchronously in each of the transfer control units. Each of the packet frames is composed of a header area and data area. The header area is used for indicating transfer control information, such as an address of a destination transfer control unit and a continuous transmission flag which denotes that the related packet frame should be exchanged to the same destination as that of the preceding packet frame.

Packet data switching system

A maintenance link is established according to a LAPD between first and second terminal units on a path through which subscribers' packet information is transmitted. In the first and second terminal units, first and second communication state control units are provided for controlling the consistency of the communication state between the two terminal units by sending/receiving communication state control information using the maintenance link.

Maintenance communication control system in an ISDN service

An ISDN D channel congestion control method has at least either a digital subscriber line circuit common (DLCC) or a signaling controller (SGC) notify either an SGC or a packet subscriber system (PSS) of a D channel congestion according to a predetermined protocol, thereby controlling the congestion of a communication controlling apparatus.

ISDN D channel congestion control method

A packet data and a header added to a head of the packet data for specifying a transfer condition of the packet data are divided together to data blocks (DBs) each having a designated data length, consisting of an initial DB including the header and an initial part of the packet data, intermediate DBs each including an intermediate part of the packet data and a last DB including a last part of the packet data, so as to be transferred to a data transfer destination in a data processor of a switching system in accordance with write commands for the initial, intermediate and last DBs respectively, and a read command for asking whether the DBs are correctly transferred is sent to the data transfer destination once, after the DBs are transferred. When the DBs are transferred, the packet data is restored at the data transfer destination only by synthesizing the transferred DBs and removing the header.

Data transfer method performed in a data processor provided in a

A boot program which can independently set the signaling links with the exchange is stored in the memory of a line concentration group. Under this boot program, a signaling controller (SGC) is used to set up a signaling link from the line concentrator to the exchange. Through the signaling link, a call processing program is transferred from the exchange side to the line concentrator side, and the transferred call processing program is used to start up the line processor in the line concentration group.

Growing community of inventors

Kawasaki, Japan

Sumie Morita