US5136643A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Public/key date-time notary facility
Assignee: Individual
•
Filing: 1990-12-20
•
Granted: 1992-08-04
•
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 17:27
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.
References Cited (Backward Citations)
US4264782A
Cited
US4386233A
Cited
US4438824A
Cited
US4458109A
Cited
US4637051A
Cited
US4799258A
Cited
US4575621A
Cited
US4625076A
Cited
US4633036A
Cited
US4710955A
Cited
US4837822A
Cited
US4897875A
Cited
US4797928A
Cited
US5001752A
Cited
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 |