Patent · US Active

Method and apparatus for generating a cryptographic time stamp for a digital document on a majority basis

US11206147B2 · kind B2 · utility

0Cited by

0References

14Claims

0Family size

Assignee

Siemens Aktiengesellschaft · DE

Inventors

Hans Aschauer · Eferding, AT
Steffen Fries · Baldham, DE
Dominik Merli · Mertingen, DE

Key dates

Filing date	Jun 27, 2018
Grant date	Dec 21, 2021
Priority date	—
Expiry date	Aug 11, 2038

Classification

Technology area (CPC H)Electricity
CPC primaryH04L9/50
WIPO fieldDigital communication
WIPO sectorElectrical engineering

Abstract

A method for producing a cryptographic timestamp for a digital document using multiple time servers is provided. In the method, a nonce value is produced and a current hash value is formed from the nonce value and the digital document. Then, a time server is repeatedly selected, the current hash value is transmitted to the selected time server, a response comprising a digital signature of the current hash value and a time indication is received by the selected time server, and an additional hash value is determined from the received response and used as the current hash value. The cryptographic timestamp for the digital document is formed from the nonce value and the multiple received responses. The method produces a tamperproof timestamp on a majority basis and is suitable for dating and protocolling in the field of automation and IoT.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.