Hitachi, Ltd.

Nippon Telegraph and Telephone Corporation

Hitachi Communication Systems, Inc.

Hitachi Communications Systems, Inc.

Kenji Kawakita

Masao Kunimoto

Jiro Kashio

Shinobu Gohara

Shinichi Iwaki

Satoshi Shimizu

Naoya Ikeda

Takanori Miyamoto

Takashi Nishikado

Hidehiro Fukushima

Masashi Hiraiwa

Tatsuo Mochinaga

Sakae Miki

Kenji Kawaguchi

Kenji Iimura

Kenichi Kimura

Masashi Kamegaya

Satoru Inazawa

Hiroshi Takahashi

Satoshi Miyazaki

Shiro Baba

Yasushi Akao

Susumu Matsui

Noboru Endo

Osamu Takada

Shigeru Miyake

Toshio Okochi

Satoru Tezuka

Matsuaki Terada

Shirou Tanabe

Takeshi Harakawa

Tetsuo Takemura

Kunio Hiyama

Shunji Shimada

Takashi Kagei

Keizo Mizuguchi

Akira Mineo

Hisao Sasaki

Seiji Kamada

Yutaka Torii

Michio Hara

Hiroyuki Ichikawa

Isao Fukuta

Kenjirou Yasunari

Akira Ikuta

Hiroshi Izuha

A communication network including connection switching exchanges, such as an ATM, a connection management apparatus is provided in a network management unit of a communication network. A group of logical connections with a fixed group size and consecutive identifiers assigned to the connections is treated as a unit. The number of logical connections in the group is an integer with a power of 2. The logical connections and connection identifiers assigned to the logical connections are set up and released in connection setting units each equal to a multiple of the group size in a unitary manner across the network. A priority level is assigned to each connection setting unit. When logical connections have been set for connection setting units sharing the same connection identifiers, logical connections with the shared connection identifiers pertaining to a connection setting unit with a smaller size is considered to be valid.

Connection switching apparatus, connection switching network contol system and connection switching network control method

A signal processing method for an ATM switching network formed by connecting a plurality of ATM switching networks in which header conversion tables of line interfaces can be rewritten by control cells, includes in response to occurrence of an abnormality in a call control processor of a ATM switching system A, informing an ATM switching system B of the occurrence of the abnormality, transferring call control information in the ATM switching system A to the ATM switching system B, rewriting header conversion tables included in a plurality of line interfaces of the ATM switching system A by using control cells generated by the ATM switching system A and thereby transferring signal channel cells arriving at the ATM switching system A after occurrence of the abnormality to the ATM switching system B, and rewriting header conversion tables included in a plurality of line interfaces of the ATM switching system A by using control cells generated by the ATM switching system B and thereby making a call control processor of the ATM switching system B effect route control of information channel cells within the ATM switching system A.

ATM switching network and ATM switching system in which the transfer of inputted cells is controlled by control cells, and signal processing method in ATM switching network

In a communication network including connection switching exchanges such as an ATM, a connection management means is provided in a network management unit of the communication network. A group of logical connections with a fixed group size and consecutive identifiers assigned to the connections is treated as a unit. The number of logical connections in such a group is an integer with power of 2. Logical connections in the communication network and connection identifiers assigned to the logical connections are set up and released in connection setting units each equal to a multiple of the group size in a unitary manner across the whole communication network. A priority level is assigned to each connection setting unit. When logical connections have been set for a plurality of connection setting units sharing the same connection identifiers, logical connections with the shared connection identifiers pertaining to a connection setting unit with a smallest size is considered to be valid.

Connection switching apparatus, connection switching network control system and connection switching network control method

A router device facilitates management of connection of a manager and assures communication quality of each of the connections. The router device determines a communication quality required by the communication of the packet in reference to a protocol information, an application acknowledging information and a priority information, transmits the control packet having the determined communication quality set therein to another router device contained in the same connection and further performs a traffic control (a preferential processing of a packet or the like) satisfying a communication quality indicated by the transmitted or received control packet in respect to the packet of the aforesaid connection.

Router device and network system using the same

ATM switching network and ATM switching system in which the transfer of

A cell/packet assembly and disassembly apparatus is provided for efficiently connecting a line in a line switching system to an ATM network or a packet network, without causing congestion, to transmit and receive cells or packets therebetween. The cell/packet assembly and disassembly apparatus, upon detecting a call setting request outputted from a line switch board in response to a call originated from a terminal, starts cell assembly and cell disassembly of user information transmitted and received between a channel on a line in the line switching system corresponding to the call setting request and a virtual channel on the ATM network assigned to the channel. Also, when detecting a call setting request outputted from a predetermined virtual channel in the ATM network, the packet or cell assembly and disassembly apparatus starts cell assembly and cell disassembly of user information transmitted and received between the virtual channel on the ATM network corresponding to this call setting request and a channel on a line in the channel switching system assigned to the virtual channel.

Cell/packet assembly and disassembly apparatus and network system

A system is provided for building, operating, and managing a virtual network which integrates the configuration, the operation, and the management of plural information devices connected to a network. The system includes agents for operating, and managing information devices in the respective devices, a physical manager for building, operating, and managing the information devices, and a logical manager for logically building, operating, and managing the information devices. The agent operates to control the settings and the change of the information device in which the agent is mounted and communicates the information with the physical manager. The physical manager operates to manage the agent of each information device and communicates the information with a user and the logical manager. The logical manager operates to build, operate, and manage the directory services, the users, and so forth and, when these directories and user are newly set or changed, to communicate the information about the new settings and the change with the physical manager.

Management system for updating network managed by physical manager to

A cell/packet assembly and disassembly apparatus is provided for efficiently connecting a line in a line switching system to an ATM network or a packet network, without causing congestion, to transmit and receive cells or packets therebetween. The cell/packet assembly and disassembly apparatus, upon detecting a call setting request outputted from a line switch board in response to a call originated from a terminal, starts cell assembly and cell disassembly of user information transmitted and received between a channel on a line in the line switching system corresponding to the call setting request and a virtual channel on the ATM network assigned to the channel. Also, when detecting a call setting request outputted from a predetermined virtual channel in the ATM network, the packet or cell assembly and disassembly apparatus starts cell assembly and cell disassembly of user information transmitted and received between the virtual channel on the ATM network corresponding to this call setting request and a channel on a line in the channel switching system assigned to the virtual channel. Further, when detecting the reception of a call disconnect request from the line switch board or from a predetermined virtual channel in the ATM network, the packet or cell assembly and disassembly apparatus stops the cell assembly and the cell disassembly of the user information transmitted and received between the corresponding virtual channel and the channel on the line in the line switching system.

Cell/ packet assembly and disassembly apparatus and network system

An ATM switch capable of preventing the network resource from being wasted during the occurrence of an overcrowding condition. In the ATM switch, both a message type and a processing mode are stored in correspondence to the connections. When the discarding of a cell occurs, the connection to which the discarded cell belongs is set to a discard mode by a cell discard controlling circuit, and each cell constituting the same message as that of the discarded cell out of the subsequent cells is discarded, and when a demarkation of the message has been detected, the processing mode is returned to a transfer mode, whereby the subsequent received cells are transferred in a normal manner. Thus, the cell which has become useless for a reception terminal is discarded in the network.

ATM switch

Information of a plurality of operation modes is stored in memory. Information of temporary protocols and true protocols is associated with event numbers and processing state numbers, then stored in a status transition table circuit. When an event number and a processing state number are set in an input register, a CPU selects a temporary protocol according to the event number and processing state number. Then, the CPU retrieves an operation mode associated with the temporary protocol from memory, selects a true protocol according to the retrieved operation mode, then executes information processing according to the true protocol.

Communication control system and information processing system

A system of adding an operand address included in an instruction word to the contents of a modification register to obtain an effective address, wherein address data which designates each of a plurality of data tables constituted with prescribed storage capacity, is stored in a plurality of modification registers. Prescribed address data of one of the plurality of modification registers is selected based on the instruction word. The effective address for addressing the operand is obtained by adding the prescribed address data of the one of the plurality of modification registers to address data included in the operand address. The address data included in the operand address designates addresses which correspond to addresses of the plurality of data tables.

Operand address modification system

A multichannel communication processing system having line control apparatus means for analyzing receiving frames and channel-controlling transmitting frames, DMA control apparatus for transferring the data not via a host processor but directly to a main memory, a memory for storing a variety of data and a communication protocol processing program, a CPU for controlling the communication processing system as a whole and line correspondence apparatus including line correspondence units provided between the lines and the line control apparatus whereby serial interfaces with channels of the plurality of lines are effected.

Multichannel communication processing system

An adaptation processing apparatus for assembling received data units of a fixed length to provide variable length data units and transmitting the variable length data units to a plurality of variable length data unit processors while assembling variable length data units received from said plurality of the variable length data unit processors to provide fixed length data units for transmission thereof. An ATM switching system includes the adaptation processing apparatus, a signal processing unit including the plurality of variable length data unit processors mentioned above, and first-in first-out mechanisms for the variable length data units provided in the adaptation processing apparatus in association with every one of the plural variable length data unit processors.

ATM switching system and adaptation processing apparatus

In a network system in which an interconnection is achieved between an LAN terminal connected to an LAN and an ISDN terminal linked with an ISDN via at least an LAN/ISDN inter-working unit coupling the LAN with the ISDN, the ISDN terminal develops a function to multiplex data link connections (communication paths) identified with respective data link connection identifiers (DLCIs) on ISDN channels. After conducting a call establishment to the ISDN terminal, the inter-working unit supplies the LAN terminal with an ISDN channel number and a DLCI designating an ISDN communication path. Thereafter, the LAN terminal sends an LAN frame having an OSI layer 2 header loaded with the communication path information to the inter-working unit. On receiving the LAN frame, the inter-working unit executes a format conversion to convert the LAN frame into an ISDN frame based on the ISDN communication path information.

Interconnection system and method for heterogeneous networks

Growing community of inventors

Urawa, Japan

Kenji Kawakita