Patent ID: 8051490

Claim:
A computer system comprising: a storage system for storing data; a terminal for using the data; a management server coupled to the storage system and the terminal; and a positioning module for identifying a location of the terminal, wherein the storage system comprising: a first interface coupled to the management server; a first processor coupled to the first interface; a first memory coupled to the first processor; and a first storage device for storing the data, wherein the terminal comprising: a second interface coupled to the management server; a second processor coupled to the second interface; and a second storage device for storing a copy of the data which includes a volatile storage area and a nonvolatile storage area, wherein the management server comprising: a third interface coupled to the storage system and the terminal; a third processor coupled to the third interface; and a third memory coupled to the third processor, wherein the terminal is configured to: identify the location of the terminal by the positioning module in a case of using the data; transmit terminal information including the identified location of the terminal to the management server; and transmit a usage request for the data to the management server, wherein the management server is configured to: judge whether or not use of the data is to be permitted based on the terminal information; and transmit permit information including usage conditions for the data to the terminal in a case where the use of the data is to be permitted, wherein the terminal is further configured to: select at least one of the volatile storage area and the nonvolatile storage area based on the usage conditions; and store the copy of the data in the selected storage area, wherein the storage system is further configured to encrypt data to be used by the terminal and transmits the encrypted data, wherein the permit information includes a decryption key for decrypting the encrypted data, and wherein the terminal is further configured to select at least one of the volatile storage area and the nonvolatile storage area based on the usage conditions for the requested data, and stores the decryption key in the selected storage area.