(54) PIECEWISE LOGICAL DATA MANAGEMENT (75) Inventor: Charles A. Milligan, Golden, CO (US)
(73) Assignee: Storage Technology Corporation,
Louisville, CO (US)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 272 days.
(21) Appl.No.: 11/485,148
(22) Filed: Jul. 12, 2006
(51) Int. CI.
G06F13/00 (2006.01)
(52) U.S. CI 711/154; 711/216
(58) Field of Classification Search 711/154,
711/216
See application file for complete search history. (56) References Cited
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Microsoft Press Computer Dictionary, 3rd Edition by Microsoft Press, 1997, p. 145*
* cited by examiner
Primary Examiner—Reba I Elmore
(74) Attorney, Agent, or Firm—Brooks Kushman PC.
(57) ABSTRACT
A method for storing data that is reconstructable in a piecewise manner comprises receiving a user data unit in the form of a data stream to be stored in the data storage system. A plurality of logical data units associated with the user data unit are then identified. A digital signature is associated with each logical data unit and stored within a component of the data storage system. The logical data unit digital signature is used by the data storage system to determine whether or not to actually store each logical data unit. A digital signature for the entire user data unit is also determined and associated with the user data unit. A reconstructed user data unit when desired is then assembled by examining the stored logical data unit digital signatures.
18 Claims, 7 Drawing Sheets
