Method and system for data retention

• US 20070276843A1
• Filed: 04/28/2006
• Published: 11/29/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: Eshghi, Kave, Lillibridge, Mark
• Granted Patent: US 9,195,665 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/113 Details of archiving lifecycle management in storage systems G06F3/0649; backup systems G06F11/1446
• CPC Class Codes: G06F 16/125 characterised by the use of retention policies retention policies for HSM systems G06F16/185

Abstract

Embodiments of the present invention relate to a system and method of document retention with policy-controlled deletion. Embodiments of the present invention comprise committing to a plurality of documents, deleting one of the plurality of documents, and providing a proof of authorized deletion of the one of the plurality of documents in response to an audit request.

Claims

1. A method of data retention, comprising:

committing to a plurality of documents;

deleting one of the plurality of documents; and

providing a proof of authorized deletion of the one of the plurality of documents in response to an audit request.

2. The method of claim 1, further comprising receiving a deletion request and verifying that the deletion request is authorized.

3. The method of claim 2, wherein verifying that the deletion request is authorized includes verifying that the deletion request complies with a deletion policy.

4. The method of claim 3, wherein the deletion policy is an accounting policy, a legal policy, a business policy, a tax policy, a government policy, or a retention time policy.

5. The method of claim 1, further comprising verifying that a deletion request complies with a deletion policy for a specified data category selected from a plurality of deletion policies corresponding to a plurality of data categories.

6. The method of claim 1, further comprising automatically deleting data in response to a time deletion policy.

7. The method of claim 1, further comprising logging instances of document deletion.

8. The method of claim 1, further comprising maintaining a list of current and past deletion policies for authorization of deletion requests, the list of current and past deletion policies facilitating a determination of which policy is in effect at a given time.

9. The method of claim 8, further comprising verifying that a deletion request is authorized, wherein verifying that the deletion request is authorized includes verifying that the deletion request complies with a designated deletion policy in effect at the time of the deletion request as designated by the list of current and past deletion policies.

10. The method of claim 1, further comprising:

receiving a request to switch to a new deletion policy; and

,

verifying that the request to switch is authorized.

11. The method of claim 1, further comprising storing a deletion request for use as part of the proof of authorized deletion.

12. The method of claim 1, wherein committing to the plurality of documents comprises building and publishing a hash-based directed acyclic graph using information from the plurality of documents.

13. The method of claim 12, further comprising providing the hash-based directed acyclic graph with a hash pointer to a first deletion policy, wherein the first deletion policy can be replaced by a second deletion policy having a time stamp later than the first deletion policy and having proper authorization.

14. The method of claim 13, wherein the first deletion policy is implemented as a hash-based directed acyclic graph having a plurality of nodes.

15. A method of assured document retention with controlled deletion, comprising:

storing a document in a computer archive system, the computer archive system having a hash-based directed acyclic graph to facilitate verification of storage;

dividing the document into a plurality of pieces;

receiving a request to delete a proper subset of the plurality of pieces; and

verifying that the request is authorized using information from the pieces of the plurality of pieces unrequested to be deleted.

16. The method of claim 15, wherein the document comprises a plurality of lines and the plurality of pieces includes each individual line of the plurality of lines as a separate piece.

17. The method of claim 15 wherein the plurality of pieces includes the original document as a piece.

18. The method of claim 15, wherein the plurality of pieces includes a summary of the original document as a piece.

19. The method of claim 16, wherein the summary includes one or multiple of a title of the original document, a file type of the original document, a length metric of the document, and a classification code for the original document.

20. The method of claim 15, further comprising erasing the proper subset of the plurality of pieces without erasing the other pieces of the plurality of pieces.

21. A system of assured document retention with controlled deletion, comprising:

means for committing to a plurality of documents;

means for deleting one of the plurality of documents; and

means for providing a proof of authorized deletion of the one of the plurality of documents in response to an audit request.

22. Application instructions on a computer-usable medium where the instructions, when executed, effect assured document retention with controlled deletion, comprising:

instructions configured to commit to a plurality of documents;

instructions configured to delete one of the plurality of documents; and

instructions configured to provide a proof of authorized deletion of the one of the plurality of documents in response to an audit request.

23. The application instruction of claim 22, further comprising instructions configured to maintain a list of current and past deletion policies facilitating a determination of which policy is in effect at a given time.

24. The application instructions of claim 23, wherein the deletion policy in effect is an accounting policy, a legal policy, a business policy, a tax policy, a government policy, or a retention time policy.

25. The application instructions of claim 23, further comprising instructions configured to verify that a deletion request is authorized by verifying that the deletion request complies with a designated deletion policy in effect at the time of the deletion request as designated by the list of current and past deletion policies.

26. The application instructions of claim 22, further comprising instructions configured to build and publish a hash-based directed acyclic graph using information from the plurality of documents, the hash-based directed acyclic graph having a hash-pointer to a first deletion policy, wherein the first deletion policy can be replaced by a second deletion policy having a time stamp later than the first deletion policy and having proper authorization.

27. The application instructions of claim 22, further comprising verifying that a deletion request complies with a deletion policy for a specified data category selected from a plurality of deletion policies corresponding to a plurality of data categories.

28. The application instructions of claim 22, further comprising automatically deleting data in response to a time deletion policy.

29. The application instructions of claim 22, further comprising logging instances of document deletion.

30. A method of assured document retention with controlled deletion, comprising:

committing to a plurality of documents, wherein committing to the plurality of documents comprises building and publishing a hash-based directed acyclic graph using information from the plurality of documents, the hash-based directed acyclic graph having a hash pointer to a first deletion policy, wherein the first deletion policy can be replaced by a second deletion policy having a time stamp later than the first deletion policy and having proper authorization;

deleting one of the plurality of documents;

storing a deletion request for use as part of a proof of authorized deletion;

maintaining a list of current and past deletion policies for authorization of deletion requests;

verifying that the deletion request is authorized, wherein verifying that the deletion request is authorized includes verifying that the deletion request complies with a deletion policy in the list of current and past deletion policies;

receiving an audit request for retrieval of the one of the plurality of documents after the one of the plurality of documents has been deleted;

providing the proof of authorized deletion of the one of the plurality of documents in response to the audit request;

receiving a request to switch to a new deletion policy;

verifying that the request to switch is authorized, wherein verifying that the request to switch is authorized includes retrieving information from a stored copy of the designated deletion policy in effect at the time of the request to switch as designated by the list of current and past deletion policies; and

adding the new deletion policy to the list of current and past deletion policies so that the new deletion policy is in effect.