US 7,277,541 Bl Oct. 2, 2007
METHOD AND SYSTEM FOR USING A
PORTION OF A DIGITAL GOOD AS A
Inventors: Mariusz H. Jakubowski, Bellevue, WA
(US); Ramarathnam Venkatesan,
Redmond, WA (US)
Assignee: Microsoft Corporation, Redmond, WA (US)
Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 1375 days.
Appl. No.: 09/651,424
Filed: Aug. 30, 2000
Related U.S. Application Data
Continuation-in-part of application No. 09/536,033, filed on Mar. 27, 2000, now Pat. No. 7,054,443.
H04L 9/00 (2006.01)
U.S. CI 380/37; 380/28; 380/29;
Field of Classification Search 713/1,
713/176, 189, 200-202, 190; 380/37, 44^7, 380/29, 281-284, 28 See application file for complete search history.
U.S. PATENT DOCUMENTS
A portion of a digital good is selected to be used as a substitution box (S-box) in encrypting at least another portion of a digital good. The digital good being encrypted can be the same digital good, or alternatively a different digital good, than the digital good from which the portion used as an S-box is obtained. During the encryption process, the S-box is used to substitute values of the portion being encrypted with new values (a process also referred to as "scrambling").
16 Claims, 9 Drawing Sheets