Control of access to an external storage device

An external storage device connected to a control device, comprising:

• a data storage unit that stores data;
• an attribute information storage unit that stores attribute information relating to the data, independently from the data in the data storage unit;
• and
• an output unit that outputs the attribute information in the attribute information storage unit or the data in the data storage unit according to an output request from the control device;
• wherein the external storage device is configured to stop operation of the data storage unit after a predetermined time period in a state in which its operation is not required and to reactivate the data storage unit in response to the output request from the control device to read data.

A control device for controlling access to an external storage device that comprises:

• a data storage unit for storing data;
• an attribute information storage unit for storing attribute information relating to the data independently from the data in the data storage unit;
• and an output unit for outputting the attribute information in the attribute information storage unit or the data in the data storage unit according to an output request from the control device,
• wherein
• when an instruction relating to the attribute information is input, if the storage device is at a stop, the control device activates the attribute information storage unit to fetch the attribute information,
• when an instruction to read the data from the external storage device is input, if the external storage device is at a stop, the control device activates the data storage unit to read the data;
• and
• when an instruction to write new data to the external storage device is input, if the storage device is at a stop, the control device activates the data storage unit to write the new data;
• wherein the external storage device is configured to stop operation of the data storage unit after a predetermined time period in a state in which its operation is not required.

A control method for controlling access to an external storage device, comprising:

• fetching, from the external storage device, attribute information relating to data stored in the external storage device;
• creating, in a control device, a virtual drive for storing the fetched attribute information;
• and
• controlling access to the virtual drive and the external storage device, wherein
• the access control includes:
• accessing the virtual drive to fetch the attribute information, when an instruction relating to the attribute information is input;
• activating the external storage device to read the data, when an instruction to read the data from the external storage device is input, if the external storage device is at a stop;
• and
• activating the external storage device to write new data, when an instruction to write the new data to the external storage device is input, if the external storage device is at a stop;
• wherein the external storage device stops operation at a predetermined time after operation of the external storage device is not required and reactivated to perform a read or a write.

A control method of an external storage device connected to a control device, comprising:

• storing data in a data storage unit in the external storage device,
• storing, in an attribute information storage unit in the external storage device, attribute information relating to the data, independently from the data in the data storage unit, and
• outputting the attribute information in the attribute information storage unit or the data in the data storage unit according to an output request from the control device;
• wherein the external storage device is configured to stop operation of the data storage unit after a predetermined time period in a state in which its operation is not required and to reactivate the data storage unit in response to the output request from the control device to read data.

A control method for controlling access to an external storage device that comprises:

• a data storage unit for storing data;
• an attribute information storage unit for storing attribute information relating to the data independently from the data in the data storage unit;
• and an output unit for outputting the attribute information in the attribute information storage unit or the data in the data storage unit according to an output request from a control device, the control method comprising:
• accessing the attribute information storage unit to fetch the attribute information, when an instruction relating to the attribute information is input;
• activating the data storage unit to read the data, if the external storage device is at a stop when an instruction to read the data from the external storage device is input;
• and
• activating the data storage unit to write new data, if the external storage device is at a stop when an instruction to write the new data to the external storage device is input;
• wherein the external storage device is configured to stop operation of the data storage unit after a predetermined time period in a state in which its operation is not required.

A computer program product for controlling access to an external storage device, the computer program product comprising:

• a computer readable medium;
• and
• a computer program stored on the computer readable medium, the computer program comprising:
• a portion for fetching, from the external storage device, attribute information relating to data stored in the external storage device;
• a portion for creating, in a control device, a virtual drive for storing the fetched attribute information;
• and
• a portion for controlling access to the virtual drive and the external storage device, wherein
• the portion for controlling access includes:
• a portion for accessing the virtual drive to fetch the attribute information, when an instruction relating to the attribute information is input;
• a portion for activating the external storage device to reads the data, if the external storage device is at a stop when an instruction to read the data from the external storage device is input;
• and
• a portion for activating the external storage device to write new data, if the external storage device is at a stop when an instruction to write the new data to the external storage device is input;
• wherein the external storage device stops operation at a predetermined time after operation of the external storage device is not required and reactivated to perform a read or a write.

A computer program product for controlling an external storage device connected to a control device, the computer program product comprising:

• a computer readable medium;
• and
• a computer program stored on the computer readable medium, the computer program comprising:
• a portion for storing data in a data storage unit in the external storage device,
• a portion for storing, in an attribute information storage unit in the external storage device, attribute information relating to the data, independently from the data in the data storage unit, and
• a portion for outputting the attribute information in the attribute information storage unit or the data in the data storage unit according to an output request from the control device;
• wherein the external storage device is configured to stop operation of the data storage unit after a predetermined time period in a state in which its operation is not required and to reactivate the data storage unit in response to the output request from the control device to read data.

A computer program product for controlling access to an external storage device that comprises:

• a data storage unit for storing data;
• an attribute information storage unit for storing attribute information relating to the data independently from the data in the data storage unit;
• and an output unit for outputting the attribute information in the attribute information storage unit or the data in the data storage unit according to an output request from a control device, the computer program product comprising:
• a computer readable medium;
• and
• a computer program stored on the computer readable medium, the computer program comprising:
• a portion for accessing the attribute information storage unit to fetch the attribute information, when an instruction relating to the attribute information is input;
• a portion for activating the data storage unit to read the data, if the external storage device is at a stop when an instruction to read the data from the external storage device is input;
• and
• a portion for activating the data storage unit to write new data, if the external storage device is at a stop when an instruction to write the new data to the external storage device is input;
• a portion for the stopping of the data storage unit after a predetermined time period in a state in which its operation is not required.