Control of access to an external storage device

1. A control device for controlling access to an external storage device comprising:

a fetching unit that fetches, from the external storage device, attribute information relating to data stored in the external storage device,

a virtual drive creation unit that creates, in the control device, a virtual drive for storing the fetched attribute information, and

an access control unit that controls access to the virtual drive and the external storage device, wherein:

when an instruction relating to the attribute information is input, the access control unit accesses the virtual drive 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 access control unit activates the external storage device to reads the data; and

when an instruction to write new data to the external storage device is input, if the external storage device is at a stop, the access control unit activates the external storage device to write the new data;

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.

2. The control device according to claim 1 , further comprising:

a stop signal output unit that, at a specified timing after the virtual drive is created, outputs to the external storage device a stop signal for stopping operations of the external storage device.

3. The control device according to claim 2 , further comprising:

a timing setting unit that sets the specified timing according to a setting instruction by a user.

4. The control device according to claim 2 , further comprising:

an activation signal output unit that, after the stop signal is output, outputs to the external storage device an activation signal to activate the external storage device, when an instruction to read the data from the external storage device or an instruction to write new data to the external storage device is input.

5. The control device according to claim 1 wherein

the virtual drive creation unit updates the attribute information in the virtual drive, when data corresponding to the attribute information is fetched from the external storage device or the new data is written to the external storage device.

6. The control device according to claim 1 wherein

the virtual drive creation unit creates the virtual drive and stores the fetched attribute information in the virtual drive, when the control device is activated.

7. The control device according to claim 1 wherein

the external storage device is a hard disk drive connected to the control device.

8. The control device according to claim 1 , further comprising:

a power supply unit that supplies power to the external storage device.

9. 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.

10. 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.

11. 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.

12. 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.

13. 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.

14. 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.

15. 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.

16. 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.