Abstract: The aim of the present invention is, as for a data communication among the nodes sharing, managing and maintaining the replicated data, to reduce the communication traffic by utilizing attributes of individual communication media. The application program of the node on the transmitting side inserts the data object into the data store, and the data synchronizer transmits an update message including the differential data and the log number. The node on the receiving side compares the log number of the update log data of its node and the log number of the update message it has received, and decides whether or not to adopt the update message.

Abstract: An IP communication system for wireless terminal which eliminates extra traffic to be used for data transfer so as to improve communication latency. The IP communication system for wireless terminal includes a control center, which controls a plurality of wireless terminals by way of a base station for communicating with an internet terminal over the Internet. The control center controls a plurality of IP addresses. The control center is provided with a database for storing the MAC addresses of wireless terminals controlled, the operating status of the respective wireless terminals controlled, and the identification of the respective base stations. The control center allocates one of the IP addresses available to a wireless terminal in the database in response to a request for communication between the wireless terminal and the internet terminal. The wireless terminal communicates with the internet terminal based on this IP address allocated.

Abstract: The agent system sends both program and data together to a destination to perform execution, and the system is provided with agent re-execution and cancelling procedures, making mission critical application possible. The non-volatile memory area is prepared in the processing system where the agent is being processed to store the executed operation log.

Abstract: A data transmission system and method in which data is automatically selected based on a processing ability of a client and a condition of a line connecting a server and the client. A terminal attribute unit collects ability characteristics of the client and a line controller collects a transmission rate of the line are provided in the server. A data attribute provider provides a proper data type and data amount of transmitting data in a profile based on the collected information on the client. A data transmission agent refers to a correspondence table and selects data with a proper data amount. Then, the data transmission agent transmits the select data to the client.

Abstract: Data transmission system and methods in which data is automatically selected based upon the processing ability of a client and the condition of a data transmission line connecting a server and the client. A terminal attribute unit that collects ability characteristics of the client and a line controller that collects the transmission rate of the data transmission line are provided in the server. A data attribute provider provides a proper data type and data amount of transmitting data in a profile based upon the collected information about the client. A data transmission agent refers to a correspondence table and selects data having a proper data amount. Then, the data transmission agent transmits the selected data to the client.

Abstract: A cache memory having four user memory areas in which different data in a main memory is to be respectively stored, and a system memory area in which shared data between programs in the user memory areas is to be stored. A data controller has a route register in which address information, such as information as to whether or not the data in the respective user memory area is replaceable and task information, is to be stored. The individual user memory areas are connected to one another via a cache internal address data bus and a user-area cache internal sub-address data bus. The internal bus is connected to a CPU bus and a memory bus via a memory management unit for performing address translation, etc.

Abstract: A high-speed large quantity data transfer system is realized using a synchronous control means having striped disks in which a synchronizing cost between disks is reduced by software control, using time-out means, and using a data transfer means where user memory is not used. An input-output processing system for inputting and outputting a large quantity of data comprising a logical disk control means, the logical disk control means comprises a performance data collection means for collecting data, a logical disk construction means for constructing a logical disk apparatus using said plurality of disk apparatus, where said logical disk construction means forms logical disk management data so that the stripe width is set in order to equalize response time needed for input and output corresponding to one stripe data of each disk apparatus constructing said logical disk apparatus; and said logical disk control means controls said logical disk apparatus by said logical disk management data.

Abstract: An incremental backup system includes a storage unit, which is accessed in block units of a predetermined size, for storing data to be backed up. Difference map information stored in the storage unit records the latest backup generation number, indicating when data in each block has been updated. A latest update generation management mechanism manages backup generation numbers for each block. A difference management mechanism inputs and stores backup data in a backup unit. The backup data includes data in a block of the storage unit which is updated in a specified backup generation based on the difference map information, a position of the block in the storage unit, and a backup generation in which the block has been updated.

Abstract: The invention provides an exclusive control unit among computers which can reliably perform an exclusive control for a shared resource while keeping a system running as a whole even if a problem occurs in any of the computers in the system. Each of the computers is connected to the others through a LAN and to a distributed shared memory bus for connecting each distributed shared memory card mounted on each computer with the others.