Fujitsu Corporation

Toshimitsu Ohba

Kiyotaka Shikata

Kenji Suzuki

Osamu Sekihata

Reiko Furuya

Toshihiro Ishida

Norihiro Yoneda

Kenji Morosawa

Shigehiro Hayashi

Michiyuki Sasaki

Tooru Kadonaga

In the case where calls made by a calling part of a first LAN connecting device are rejected by a call receiving part of a second LAN connecting device, non setting of the number of channels needed for data transmission will be detected by a channel shortage detecting block of the first LAN connecting device. In this case, an information requesting block will make a request for information of channel availability at the time of channel releasing to the second LAN connecting device. This request will be registered in the information request registering block of the second LAN connecting device. When availability of the channels accommodated in an interface is detected by the channel monitoring block of the second LAN connecting device, an information sending block will transmit channel availability information to the first LAN connecting device in accordance with the request registered in the information request registering block.

LAN connecting device and LAN connecting system

A keep call back device for connecting calls between subscribers includes a first call establishing portion for establishing a first call by connecting a call received from a calling terminal to a called terminal when it recognizes the call from the calling terminal which is able to respond to a call from one terminal without ending communication with another terminal during communication with another terminal, a second call establishing portion for establishing a second call by placing a call to the calling terminal after the first call has been established, and a call releasing portion for releasing the first call by disconnecting the same when the second call is established.

Keep call back device

A LAN-WAN-LAN communication method and apparatus for performing communication between a LAN on a transmitting side and a LAN on a receiving side via a wide area network within limits of an allocated band includes a demultiplexer/multiplexer unit for demultiplexing data, which has been received from the LAN on the transmitting side, into data constituting the smallest units of information and transmitting this data via a plurality of lines. Then, data, which is sent to the receiving side via each line, is multiplexed on the receiving side and the multiplexed data is sent to the LAN on the receiving side. A traffic monitoring unit is provided for monitoring traffic between LANS. A band is obtained, which is required for communication between LANs based upon the traffic. Communication between LANs is performed by increasing, decreasing or maintaining the number of lines, which are used in communication between LANS, based upon the obtained band.

LAN-WAN-LAN communication method, and apparatus for LAN-WAN connection

An admission managing system manages admission of a card holder of an integrated circuit card which has a part for operating by a power induced by an external command, a memory for storing identification information and a part for at least communicating in a non-contact manner including reception of the command and transmission of the identification information. The admission managing system includes a gate for admitting the card holder of the integrated circuit card when opened, a first part for transmitting the command and for receiving the identification information received from the integrated circuit card in response to the command, a second part for storing identification information of authorized card holders to be admitted, a third part for opening the gate when the identification information received by the first part from the integrated circuit card is identical to one of the identification information stored in the second part, and a fourth part for outputting a warning to the card holder if a number of times the same identification information is received by the first part from the integrated circuit card exceeds a predetermined value.

Admission managing system

An internetwork communication system provides communication from a first local area network to a second, ring-type, local area network via a bridge. The bridge receives a frame from the first local area network and transmits a dummy frame followed by a transfer frame to the second local area network. The transfer frame defines a node of the second local area network as a distant apparatus (receiver) and a node of the first local area network as a self apparatus (sender). The bridge later receives the dummy frame from the second local area network, after transmission of the dummy frame around the ring, and deletes the dummy frame and the transfer frame received following the dummy frame so that the communication in the second local area network does not circulate indefinitely around the ring. As an alternative to using a dummy frame, the bridge can receive the transfer frame, after circulation around the second local area network, and compare the distant apparatus of the received internetwork transfer frame with a stored distant apparatus address. When the received distant apparatus address matches the stored distant apparatus address, the bridge deletes the transfer frame from the second local area network.

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Kawasaki, Japan

Toshimitsu Ohba