0422757-A2 is referenced by 30 patents and cites 1 patents.

A time notarization apparatus and method is disclosed which uses a secure, microprocessor based hardware platform which performs public kay cryptographic 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 (4) and a stable, secure storage device (8) to record the private half of a public/private key pair. Coupled to both the digital clock (4) and the storage device (8) is a data processing device (6) which performs public key signature operations in a secure and tamper-proof manner. Only the processing device (6) has access to the secure storage device (8) 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 hadware platform also includes a power source (12), (e.g., an on-board battery) to ensure the accuracy of the device's digital clock (4) and the security of storage data prior to installation or in case of a power failure.

Title
Public/key date-time notary facility.
Application Number
EP19900305778 19900529
Publication Number
0422757 (A2)
Application Date
May 29, 1990
Publication Date
April 17, 1991
Inventor
Fischer Addison M
US
Assignee
Fischer Addison M
US
IPC
H04L 09/32
H04L 09/32
H04L 09/00
G09C 01/00
G07F 07/12
G06F 21/20
G06F 21/00
G06F 17/21
G06F 01/14
H04L 09/32
H04L 09/00
G09C 01/00
G07F 07/12
G06F 21/20
G06F 21/00
G06F 17/21
G06F 01/14
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