Nec Corporation

Jun-ichi Yamato

Akihisa Kenmochi

Masaki Kan

Yuji Kaneko

Satoshi Onodera

Yoshihide Kikuchi

Hiroshi Matoba

Hidetaka Hane

Takuya Nishibayashi

Hisayuki Aoki

A replication system rapidly switches from a normal-system site to a standby-system site in the event of a problem and reliably maintains functions, and moreover, reduces drops in performance. A first site provides system functions that accompany writing and reading of data. A relay transfer device receives update information from the first site, causes completion of processes for replication in the first site, and continuously executes processes for successively transferring the update information to a second site. The second site receives the update information of the first site and applies this update information to itself to retain a replica of the data of the first site. If, when executing a write request command or a read request command to provide at least a portion of the system functions, the second site has not yet retained the most recent data that are the target of the command, the second site acquires the necessary update information and then executes the command.

Replication system having the capability to accept commands at a standby-system site before completion of updating thereof

As in a normal storage system, an application run on a host issues a data write command or a data read command. A monitor unit monitors the host and a command issued by the host to detect a re-startable point to issue the re-startable point notification to a source storage system. Using the re-startable point as a momentum, the source storage system converts a command stored in a buffering unit into a command for transfer in which redundant data transfer has been curtailed to transfer the command for transfer to a destination storage system. The destination storage system applies the received command to a storage unit. At this time, the command for transfer is restored to an ordinary command which is applied.

Storage system and method for data replication with reduced redundant data transfer

A broadcast storage system is disclosed which is easily controllable by the user for setting programs for timer recording and playing back recorded programs. The broadcast storage system has one or more slave apparatus and a master apparatus. The master apparatus grasps programs set for timer recording by each of the slave apparatus. When a program to be recorded is determined by the user or an automatic timer recording process, the master apparatus selects an apparatus to record the program such that a plurality of timer recording settings are not made at one time in one apparatus, and instructs the selected apparatus to set the program for timer recording. When instructed to set the program for timer recording, a slave apparatus sets the program for timer recording, and records the program at the time when the program is broadcast.

Broadcast storage system with reduced user's control actions

A program processing apparatus and system is disclosed by which an electronic program guide can be used to confirm a condition of each program readily and perform various operations for a program. The program management apparatus is formed from a personal computer having functions for performing recording and playback of a program, a video tape recorder having a function for acquiring an electronic program guide, or a like apparatus. The program management apparatus includes a program recording section, a program playback section, a program guide displaying section which issues an instruction to perform a suitable program process in response to an operation of an electronic program guide displayed thereon, a recording reservation management section, and a program guide preparation section for preparing an electronic program guide. The program management apparatus further includes a program guide database, a program recording reservation database and a recorded program database.

Program processing apparatus, program processing system, and program

A relaying device for relaying data transferred from first storage unit to a second storage unit, is provided outside a range presumed to be affected by a disaster, when a disaster, such as an earthquake, has broken out in an installation site of a host of a normal system (host computer) and the first storage unit. Moreover, the relaying device is placed at such a location that the data transfer time between the first storage unit and the relaying device is shorter than the data transfer time in case the first and second storage units directly transfer data with each other. On receipt of data from the first storage unit, the relaying device notifies the first storage unit of the completion of reception of the data before completing transmission of the data to the second storage unit.

Data copying system, relaying device, data transfer/reception system and program for copying of data in storage unit

A program recording devicecompresses data of program recorded in a hard disk, at a user's desirable timing in a user's desirable compression level. A recording unitrecords data of a program, and a re-compression schedulerincludes a compression setting table having a re-compression condition and an encoding method used in a compressing process. The re-compression condition and the encoding method are, in advance, established for each compressing timing. Then the scheduleris activated in a predetermined interval and selects a program satisfying the re-compression condition among programs recorded by the recording unit. The re-compressing unitcompresses data of the selected program.

Program recording device and method of recording program

A stream transfer control system including a server unit and a plurality of clients connected to each other through a network, the server unit including a plurality of transmission buffers provided corresponding to the respective clients, a read management unit for issuing a data reading request upon receiving a transfer request from a client, as well as issuing a data reading request every time a data block stored in the transmission buffer is read to empty the buffer, and a data transfer unit for reading a data block in the transmission buffer after a lapse of a fixed time since when a transfer request arrives at the read management unit and at every lapse of the fixed time from then on, thereby transferring streams to the plurality of clients over the network.

Stream transfer control system for distributing streams of moving images

A data reading device for accepting an external data transfer request, reading desired data from a storage device which stores various data and transferring the data to a sender of the data transfer request, which includes a client for issuing a reading request which designates data corresponding to a data transfer request and a time of a reading deadline of the data, a reading request sorting unit for accepting and storing an issued reading request and fetching them in descending order of reading deadlines, and a file reading unit for reading data corresponding to a reading request fetched by the reading request sorting unit from the data storage device.

Growing community of inventors

Tokyo, Japan

Jun-ichi Yamato