Abstract: In a code transmission scheme for a communication system using error correcting codes, the transmitting side generates at least one transmitting side syndrome value by carrying out a syndrome calculation for the information to be transmitted, and transmits to a receiving side at least one information packet containing the information to be transmitted and at least one redundant packet containing the transmitting side syndrome value.

Abstract: In a communication device having a function for encrypting and transferring, or receiving and decrypting contents data to be protected by copyright, an authentication and key exchange procedure with another communication device is carried out by exchanging data for the authentication and key exchange procedure directly on frames of a specific physical network or frames of a specific datalink layer network, so as to enable the encryption as the copyright protection and the decryption at the communication device and the another communication device.

Abstract: In a code transmission scheme for a communication system using error correcting codes, the transmitting side generates at least one transmitting side syndrome value by carrying out a syndrome calculation for the information to be transmitted, and transmits to a receiving side at least one information packet containing the information to be transmitted and at least one redundant packet containing the transmitting side syndrome value. Then, upon receiving at least a part of the information packet and the redundant packet, the receiving side obtains at least one receiving side syndrome value by carrying out a syndrome calculation for an information contained in the information packet as received, and performs error correction, if required, by calculating a difference between the transmitting side syndrome value contained in the received redundant packet.

Abstract: In a code transmission scheme for a communication system using error correcting codes, the transmitting side generates at least one transmitting side syndrome value by carrying out a syndrome calculation for the information to be transmitted, and transmits to a receiving side at least one information packet containing the information to be transmitted and at least one redundant packet containing the transmitting side syndrome value.

Abstract: A mobile supporting router device for realizing the handoff control associated with the moving in high speed is forms by at least one first interface connected with radio base stations, each capable of accommodating at least one mobile terminal; at least one second interface connected with a wire network; an information exchanging unit for exchanging a routing protocol on a network layer, through the second interface; a memory unit for storing information regarding a routing on the network layer based on the routing protocol exchanged by the information exchanging unit; a transfer unit for transferring datagram through the first interface according to the information regarding the routing on the network layer stored in the memory unit; a moving detection unit for detecting a moving of the mobile terminal among the radio base stations; and an information updating unit for updating the information regarding the routing on the network layer stored in the memory unit when the moving of the mobile terminal is dete

Abstract: A communication scheme for improving the performance of communications utilizing the transport layer connection provided via a radio network, by enabling a control of the transport layer connection according to the radio communication state and property of the radio terminal, without changing implementation of the transport layer of a terminal connected to a wire network. The gateway device is provided with a control unit for controlling a connection in the radio transport layer protocol according an information regarding a radio communication state of the radio terminal device, where the information regarding the radio communication state of the radio terminal device is notified from either a radio base station device covering a radio service area in which the radio terminal device is located or a home location register for carrying out at least registration and management of the radio terminal device.

Abstract: A mobile supporting router device for realizing the handoff control associated with the moving in high speed is forms by at least one first interface connected with radio base stations, each capable of accommodating at least one mobile terminal; at least one second interface connected with a wire network; an information exchanging unit for exchanging a routing protocol on a network layer, through the second interface; a memory unit for storing information regarding a routing on the network layer based on the routing protocol exchanged by the information exchanging unit; a transfer unit for transferring datagram through the first interface according to the information regarding the routing on the network layer stored in the memory unit; a moving detection unit for detecting a moving of the mobile terminal among the radio base stations; and an information updating unit for updating the information regarding the routing on the network layer stored in the memory unit when the moving of the mobile terminal is dete

Abstract: A communication scheme for improving the performance of communications utilizing the transport layer connection provided via a radio network, by enabling a control of the transport layer connection according to the radio communication state and property of the radio terminal, without changing implementation of the transport layer of a terminal connected to a wire network. The gateway device is provided with a control unit for controlling a connection in the radio transport layer protocol according an information regarding a radio communication state of the radio terminal device, where the information regarding the radio communication state of the radio terminal device is notified from either a radio base station device covering a radio service area in which the radio terminal device is located or a home location register for carrying out at least registration and management of the radio terminal device.

Abstract: A scheme for error control on AAL in ATM networks capable of realizing a reliable communication with a high throughput and a low latency. On AAL, the segmented data are sequentially written into each column of a matrix shaped data region in an interleaver, while variably setting a last column of the data region in the interleaver. Then, an error control code for the data up to the last column in each row of the data region in the interleaver is obtained and written into a corresponding location within a matrix shaped error control code region in the interleaver. The contents of each column of the data region and the error control code region in the interleaver are then read out, and a prescribed header/trailer is attached to a prescribed number of columns of the data and/or the error control codes read out from the interleaver to form a data unit.

Abstract: A switching apparatus includes an input port to which information data associated with an ATM cell is input, a memory for storing information data input via the input port, a processor for sequentially performing frame synchronization process for finding a frame and ATM cell synchronization process for checking a cell structure with respect to information data read out from the memory, and an output port for outputting information data processed by the processor.

Abstract: An ATM cell assembly and disassembly device capable of flexibly dealing with various data speeds on STM and ATM sides, and preventing the buffer overflow. In the ATM cell assembly device, the data stored in the buffer are outputted when an amount of the stored data becomes not less than a prescribed data amount sufficient for loading a payload section of each ATM cell, and the ATM cell flow is obtained from the ATM cells assembled from the data outputted from the buffer and empty cells. The buffer can be allowed to output the stored data only when the output permission signal issued in accordance with usage parameter control (UPC) parameters determined at a time of call set up is received. In the ATM cell disassembly device, the output data are stored into the buffer when a currently remaining capacity of the buffer becomes not less than an amount of data loaded in a payload section of each ATM cell, and the STM signals are obtained from the output data outputted from the buffer.