Method and apparatus for erasing data after tampering

• US 6,874,092 B1
• Filed: 09/04/2001
• Issued: 03/29/2005
• Est. Priority Date: 10/06/1998
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Original Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Inventors: Motoyama, Tetsuro, Yachida, Masuyoshi
• Primary Examiner(s): Jean, Frantz B.
• Application Number:
  US09/947,164
• Time in Patent Office: 1,302 Days
• Field of Search: 713/300, 707/203, 707/204, 707/205, 711/162, 714/6
• US Class Current: 713/300
• CPC Class Codes: G06F 21/80 in storage media based on magnetic or optical technology, e.g. disks with sectors preventing unauthorised reproduction or copying of disc-type recordable media G11B20/00
• CPC Class Codes: G11C 29/74 using duplex memories, i.e. using dual copies
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

An approach for storing and maintaining data is disclosed. One or more sensors are provided for detecting unauthorized access to a first non-volatile storage. If unauthorized access to the first non-volatile storage is detected, then the data on the first non-volatile storage is deleted by overwriting the data on the first non-volatile storage with a predetermined value so that the data cannot be recovered. The first non-volatile storage is registered with a registration authority to provide authentication of the data maintained on the first non-volatile storage.

Claims

1. A method for storing and maintaining data, the method comprising the steps of:

storing data on a storage unit in a manner that allows modification of the data only if a tamper signal is detected that indicates unauthorized physical access to the storage unit;

detecting the tamper signal; and

in response to detecting the tamper signal, deleting the data stored on the storage unit by

overwriting the data with a specified value, and

preventing any data from being written to the storage unit and preventing any data from being read from the storage unit.

2. A method as recited in claim 1, wherein the step of detecting a tamper signal includes the step of detecting a tamper signal from one or more sensors associated with the storage unit.

3. A method as recited in claim 1, wherein the step of overwriting the data with a specified value includes overwriting the data with the value OOH.

4. A method as recited in claim 3, further including the step of deleting one or more file directory entries associated with the data.

5. A method as recited in claim 1, wherein the storage unit includes one or more non-volatile storage devices containing copies of the data and the method further includes the step of deleting the copies of the data on the one or more non-volatile storage devices.

6. A method as recited in claim 1, further including the step of in response to a power failure of the storage device, performing the steps of

providing power to the storage unit from a backup power supply, and

prohibiting writing data to or reading data from the storage unit.

7. A method as recited in claim 6, further including the step of after power has been restored to the storage unit, all owing data to be written to and read from the storage unit.

8. A data storage unit for storing and maintaining data, the data storage unit comprising:

a first non-volatile storage device containing data stored thereon; and

a processing unit communicatively coupled to the first non-volatile storage device, wherein the processing unit is configured to

allow modification of the data stored on the first non-volatile storage device only if a tamper signal is detected that indicates unauthorized physical access to the first non-volatile storage device, and

in response to detecting the tamper signal,

delete the data stored on the first non-volatile storage device by overwriting the data stored on the first non-volatile storage device with a specified value, and

prevent any data from being written to the first non-volatile storage device and prevent any data from being read from the first non-volatile storage device.

9. A data storage unit as recited in claim 8, further comprising one or more sensors communicatively coupled to the processing unit for detecting physical access to the data storage unit the one or more sensors being configured to provide the tamper signal upon detecting physical access to the storage unit.

10. A data storage unit as recited in claim 8, wherein the processing unit is further configured to overwrite the data with the value 00H.

11. A data storage unit as recited in claim 8, wherein the processing unit is further configured to delete one or more file directory entries associated with the data.

12. A data storage unit as recited in claim 8, wherein the storage unit includes one or more non-volatile storage devices containing copies of the data and the processing unit is further configured to delete the copies of the data on the one or more non-volatile storage devices.

13. A data storage unit as recited in claim 8, further comprising first and second backup power supplies configured to provide power to the storage unit in the event of power loss.

14. A data storage unit as recited in claim 8, further comprising a second non-volatile storage device communicatively coupled to the processing unit, wherein a duplicate copy of data stored on the first non-volatile storage device is maintained on the second non-volatile storage device and wherein the processing unit is further configured to determine whether a failure of the first non-volatile storage device has occurred and if so, delete the data from the first non-volatile storage device by overwriting the data on the first non-volatile storage device with the specified value.

15. A data storage unit as recited in claim 8, further comprising a secure communications interface communicatively coupled to the first non-volatile storage device and configured to prevent unauthorized modification of the data stored on the first non-volatile storage.

16. A computer-readable medium carrying one or more sequences of one or more instructions for storing and maintaining data, the one or more sequences of one or more instructions including instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

storing data on a storage unit in a manner that allows modification of the data only if a tamper signal is detected that indicates unauthorized physical access to the storage unit;

detecting the tamper signal; and

in response to detecting the tamper signal, deleting the data stored on the storage unit by

overwriting the data with a specified value, and

preventing any data from being written to the storage unit and preventing any data from being read from the storage unit.

17. A computer-readable medium as recited in claim 16, wherein the step of detecting a tamper signal includes the step of detecting a tamper signal from one or more sensors associated with the storage unit.

18. A computer-readable medium as recited in claim 16, wherein the step of overwriting the data with a specified value includes overwriting the data with the value 00H.

19. A computer-readable medium as recited in claim 18, further including the step of deleting one or more file directory entries associated with the data.

20. A computer-readable medium as recited in claim 16, wherein the storage unit includes one or more non-volatile storage devices containing copies of the data and the method further includes the step of deleting the copies of the data on the one or more non-volatile storage devices.

21. A computer-readable medium as recited in claim 16, further including the step of in response to a power failure of the storage device, performing the steps of providing power to the storage unit from a backup power supply, and prohibiting writing data to or reading data from the storage unit.

22. A computer-readable medium as recited in claim 21, further including the step of after power has been restored to the storage unit, allowing data to be written to and read from the storage unit.