US5473687A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for retrieving secure information from a database
Assignee: Xylon LLC
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Filing: 1993-12-29
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Granted: 1995-12-05
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Expires: 2013-12-29
Abstract
Abstract A system for retrieving a packet of informational digital data which is stored on a secure storage medium. The informational data packet (IDP) is read from the secure storage medium and then expanded in length to form a sequence of digital data which is so large as to be inconvenient for permanent storage.
Inventors
- 👤 Thomas H. Lipscomb
- 👤 Robert H. Nagel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:21
CPC Classifications
G; G06; G06F; G06F21/00; G06F21/60; G06F21/62; G06F21/6209; G06F21/70; G06F21/78; G06F21/80; G06F2211/00; G06F2211/007; G11; G11B; G11B20/00; G11B20/00086; G11B20/00666
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
144 words
A method of retrieving a packet of informational digital data which is stored in encrypted form, said method comprising the steps of: (a) retrieving the stored informational data packet (IDP); (b) decrypting the IDP into a first sequence of digital data; (c) expanding the first sequence of digital data into a second sequence of digital data which is so large as to be inconvenient for permanent storage, said expanding step including the step of embedding said first sequence of digital data in a series of pseudorandom digital data which is substantially equal to 1-5 megabytes or more in length, such that said second sequence is substantially equal to 1.5 megabytes or more in length and is not compressible; (d) storing said second sequence of digital data; (e) retrieving the stored second sequence of digital data; and (f) extracting the IDP from said second sequence.
Claim 2
Independent Claim
144 words
A method of retrieving a packet of informational digital data which is stored in encrypted form, said method comprising the steps of: (a) retrieving the stored informational data packet (IDP); (b) decrypting the IDP into a first sequence of digital data; (c) expanding the first sequence of digital data into a second sequence of digital data which is so large as to be inconvenient for permanent storage, said expanding step including the step of embedding said first sequence of digital data in a series of pseudorandom digital data which is substantially equal to 1-5 megabytes or more in length, such that said second sequence is substantially equal to 1.5 megabytes or more in length and is not compressible; (d) storing said second sequence of digital data; (e) retrieving the stored second sequence of digital data; and (f) extracting the IDP from said second sequence.
Claim 3
Dependent Claim
27 words
The method defined in claim 1, wherein said first sequence of digital data is embedded in a different way during each successive execution of said expanding step.
Claim 4
Dependent Claim
44 words
The method defined in claim 1, wherein said embedding step includes the steps of obtaining a key and a random number generating algorithm which requires a key, and thereafter executing said random number generating algorithm with said key to produce said pseudorandom digital data.
Claim 5
Dependent Claim
15 words
The method defined in claim 3, wherein said key is obtained from an external source.
Claim 6
Dependent Claim
59 words
The method defined in claim 3, wherein a plurality of IDPs are stored in encrypted form on a storage medium having a file directory stored thereon indicating the identity, location and length of each IDP, and wherein said step of obtaining said key includes the steps of reading said file directory and determining said key from information contained therein.
Claim 7
Dependent Claim
25 words
The method defined in claim 5, wherein said key is determined from information contained in said file directory relating to the IDP to be decrypted.
Claim 8
Dependent Claim
28 words
The method defined in claim 3, wherein said information data packet (IDP) is stored on a storage medium and wherein said key is obtained from said storage medium.
Claim 9
Dependent Claim
42 words
The method defined in claim 3, wherein said information data packet (IDP) is stored on a storage medium with a file directory which contains the identity, location and length of said IDP, and wherein said key is obtained from said file directory.
Claim 10
Dependent Claim
19 words
The method defined in claim 3, wherein said random number generating algorithm is the Data Encryption Standard (DES) algorithm.
Claim 11
Dependent Claim
20 words
The method defined in claim 3, wherein said random number generating algorithm is formed by a linear feedback shift register.
Claim 12
Dependent Claim
69 words
The method defined in claim 1, wherein said information data packet (IDP) is stored on a storage medium in a plurality of blocks each of a prescribed length, and wherein said packet is combined, block by block, with said pseudorandom digital data to expand the bit length of each block such that the total length of all expanded blocks of data is substantially equal to 1.5 megabytes or more.
Claim 13
Dependent Claim
22 words
The method defined in claim 1, wherein said length of said second sequence is greater than the largest hand-held, removable storage medium.
Claim 14
Dependent Claim
18 words
The method defined in claim 1, wherein said embedding step is unique each time said packet is expanded.
Claim 15
Dependent Claim
25 words
The method defined in claim 1, wherein the bit length of said pseudorandom digital data is equal to the bit length of said second sequence.
Claim 16
Dependent Claim
27 words
The method defined in claim 1, wherein the bit length of said second sequence is equal to at least twice the bit length of said first sequence.
Claim 17
Dependent Claim
32 words
The method defined in claim 14, wherein the bit length of said second sequence is equal to at least said twice the bit length of said first sequence plus two binary digits.
Claim 18
Dependent Claim
44 words
The method defined in claim 1, wherein said step of extracting the IDP from said second sequence includes the steps of: (e) producing said pseudorandom digital data; and (f) combining said pseudorandom digital data with said second sequence to produce said information data packet.
Claim 19
Dependent Claim
39 words
The method defined in claim 17, wherein said combining step (f) includes the steps of: (1) logically combining said pseudorandom data with said second sequence by exclusive-or to produce a result; and (2) scanning said result for binary one's.
References Cited (Backward Citations)
US4994008A
Cited
US5195136A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-12-04 | 1999-06-05 | 1999-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-12-04 | 2003-06-05 | 2003-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-12-04 | 2007-06-05 | 2007-12-05 | $7700.00 | Window Closed / Lapsed |