Patent US5136643A successfully refreshed from Google Patents.
US5136643A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Public/key date-time notary facility
Assignee: Individual
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Filing: 1990-12-20
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Granted: 1992-08-04
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Expires: 2010-12-20
Abstract
Abstract A time notarization apparatus and method is disclosed which uses a secure, microprocessor based hardware platform which performs public key crytographic operations to obtain trusted time stamping with a minimum of intervention by third parties. The hardware platform is encapsulated in a secure fashion so that the device's timestamping mechanism may not be readily tampered with or altered. The hardware platform includes at least one digital clock and a stable, secure storage device to record the private half of a public/private key pair. Coupled to both the digital clock and the storage device is a data processing device which performs public key signature operations in a secure and tamper-proof manner. Only the processing device has access to the secure storage device and its associated private key. The hardware platform also includes input/output means which receives a digital message which is to be digitally signed and timestamped and which outputs the resulting timestamped signature generated by the device. The hardware platform also includes a power source, (e.g., on on-board battery) to ensure the accuracy of the device's digital clock and the security of storage data prior to installation or in case of a power failure.
Inventors
- 👤 Addison M. Fischer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:15
CPC Classifications
G; G07; G07F; G07F7/00; G07F7/08; G07F7/12; H; H04; H04L; H04L9/00; H04L9/32; H04L9/321; H04L9/3297; H04L2209/00; H04L2209/56
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
124 words
A digital time notarization device for enabling a user to digitally notarize digital information without regard to any particular recipient of said digital information comprising: a clock module for generating clock signals indicative of time; input means for receiving a digital input value to be notarized; a digital storage device, said storage device storing a private key associated with the notarization device, said private key having a corresponding device public key; and a digital processor device for performing a digital signature operation on said clock signals and said digital input value using said private key corresponding to the device public key for generating a notarization time stamp, whereby a holder of said device public key may verify that said notarized time stamp is authentic.
Claim 2
Dependent Claim
124 words
A digital time notarization device for enabling a user to digitally notarize digital information without regard to any particular recipient of said digital information comprising: a clock module for generating clock signals indicative of time; input means for receiving a digital input value to be notarized; a digital storage device, said storage device storing a private key associated with the notarization device, said private key having a corresponding device public key; and a digital processor device for performing a digital signature operation on said clock signals and said digital input value using said private key corresponding to the device public key for generating a notarization time stamp, whereby a holder of said device public key may verify that said notarized time stamp is authentic.
Claim 3
Dependent Claim
37 words
A device according to claim 1, further comprising random number generator means, coupled to said processor device for generating a relatively unpredictable output value, said processor device creating said notarized time stamp using said unpredictable output value.
Claim 4
Dependent Claim
16 words
A device according to claim 1, wherein said clock module includes a plurality of digital clocks.
Claim 5
Dependent Claim
40 words
A device according to claim 3, further including averaging means coupled to receive the outputs of said plurality of digital clocks for generating a time output signal which is the average of the outputs of said plurality of digital clocks.
Claim 6
Dependent Claim
31 words
A device according to claim 3, further including threshold detecting means for generating an error signal if the difference between the outputs of said plurality of clocks exceeds a predetermined threshold.
Claim 7
Dependent Claim
16 words
A device according to claim 1, wherein said input value represents at least one digital message.
Claim 8
Dependent Claim
15 words
A device according to claim 1, wherein said digital input value is a hash value.
Claim 9
Independent Claim
113 words
A method of digitally time notarizing a digital message comprising the steps of: receiving a digital message to be date/time notarized by a digital notarization device; generating clock signals indicative of time within said device; accessing a private key created for said device and stored in a tamper proof storage device in said notarization device, said private key having a corresponding device public key; performing a digital signature operation on said digital message, and said clock signals, using said private key, whereby a notarized time stamp is generated by said notarization device; and generating a digital time stamp notarization packet including said notarized time stamp and digital data identifying said device public key.
Claim 10
Independent Claim
113 words
A method of digitally time notarizing a digital message comprising the steps of: receiving a digital message to be date/time notarized by a digital notarization device; generating clock signals indicative of time within said device; accessing a private key created for said device and stored in a tamper proof storage device in said notarization device, said private key having a corresponding device public key; performing a digital signature operation on said digital message, and said clock signals, using said private key, whereby a notarized time stamp is generated by said notarization device; and generating a digital time stamp notarization packet including said notarized time stamp and digital data identifying said device public key.
Claim 11
Dependent Claim
42 words
A method according to claim 8, wherein said device public key is certified by a trusted authority and wherein said notarization packet includes at least a notarized time stamp and a digital certificate by the trusted authority certifying the device's public key.
Claim 12
Dependent Claim
26 words
A method according to claim 8, further including the steps of: generating a relatively unpredictable value, and crating said notarized time stamp using said unpredictable value.
Claim 13
Dependent Claim
23 words
A method according to claim 8, wherein said receiving step includes the step of receiving said digital message from a data processing system.
Claim 14
Dependent Claim
29 words
A method according to claim 8, further including the steps of initializing said notarization device; and storing an indication in said notarization device that the initialization has been completed.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-04 | 1996-02-03 | 1996-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-04 | 2000-02-03 | 2000-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-04 | 2004-02-03 | 2004-08-04 | $7700.00 | Window Closed / Lapsed |