US 6,983,365 B1
Encryption systems and methods for identifying and coalescing identical objects encrypted with different keys
John R. Douceur, Bellevue, Wash. (US); William J. Bolosky, Issaquah, Wash. (US); and Marvin M. Theimer, Bellevue, Wash. (US)
Assigned to Microsoft Corporation, Redmond, Wash. (US)
Filed on May 05, 2000, as Appl. No. 9/565,821.
Int. Cl. H04L 9/00 (2006.01)
U.S. Cl. 713—165 37 Claims
OG exemplary drawing
 
1. An encryption method comprising:
computing a representation for each of two or more encryptable objects;
encrypting each of the encryptable objects using its own representation as an encryption key, said encrypting defining a plurality of cipher objects each of which corresponds to an encryptable object;
ascertaining from the cipher objects whether the corresponding encryptable objects are identical; and further comprising:
encrypting each representation with a different key to provide a plurality of encrypted representations;
defining individual key identifiers;
associating each of the key identifiers with an individual key; and
building a plurality of ordered tuples, each of which comprises:
a single cipher object that represents all of the two or more encryptable objects;
at least one key identifier; and
at least one encrypted representation each of which being associated with a corresponding key identifier.