System and method for providing trusted time in content of digital data files

• US 20050160272A1
• Filed: 12/01/2004
• Published: 07/21/2005
• Est. Priority Date: 10/28/1999
• Status: Abandoned Application

• Current Assignee: Timecertain LLC
• Original Assignee: Timecertain LLC
• Inventors: Teppler, Steven W.
• Application Number:
  US11/000,424
• Publication Number:
  US 20050160272A1
• Time in Patent Office: Days
• US Class Current: 713/178
• CPC Class Codes: H04L 2209/463 Electronic voting
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 2209/80 Wireless
• CPC Class Codes: H04L 9/12 Transmitting and receiving encryption devices synchronised or initially set up in a particular manner
• CPC Class Codes: H04L 9/3218 using proof of knowledge, e.g. Fiat-Shamir, GQ, Schnorr, ornon-interactive zero-knowledge proofs
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/50 using hash chains, e.g. blockchains or hash trees

Abstract

A personal computer (PC) system and methods for proving dates of digital data files, which are accessed, created, modified, received, or transmitted by the PC includes a trusted time source in a tamperproof environment, a first subsystem for saving the file at a moment in time, a second subsystem for retrieving from the trusted time source a date and a time corresponding to the moment in time, a third subsystem for appending the date and the time retrieved from the trusted time source to the saved file, a fourth subsystem for signing the saved file with the date and the time retrieved from the trusted time source appended thereto, a fifth subsystem means for hashing the signed file to produce a digest, a sixth subsystem for signing the digest with a key to produce a certificate, a seventh subsystem for appending the certificate to the saved file, and an eighth subsystem for saving the file with the certificate appended thereto. The trusted time source is a real time clock, which is not resettable, is independent of any system clock of the PC, and is installed locally relative to the PC.

Claims

1. A system for maintaining trust in a vote entered on an electronic voting machine, comprising:

a trusted time source to provide a certifiable time for an unalterable time stamp, wherein said certifiable time confirms at least one of a vote'"'"'s options, creation, receipt, or transmission;

means for receiving a request to enter the vote from a voter;

first means for saving the vote at a moment in time;

means for retrieving from said trusted time source a date and a time corresponding to said moment in time, wherein said moment in time is substantially a current time at said trusted time source corresponding to receipt of said request;

first means for appending said date and said time retrieved from said trusted time source to said saved vote;

first means for signing said saved vote with said date and said time retrieved from said trusted time source appended thereto;

means for hashing said signed vote to produce a digest;

second means for signing said digest with a key to produce a certificate;

second means for appending said certificate to said saved vote; and

second means for saving said saved vote with said certificate appended thereto.

2. The system of claim 1, wherein said first signing means comprises means for signing said saved vote with said date and same time retrieved from said trusted time source appended thereto with at least one of a voter identifier, a voter location identifier, or an electronic voting machine identifier.

3. The system of claim 1, wherein said first signing means comprises means for signing said saved vote with said date and said time retrieved from said trusted time source appended thereto with a voting machine identifier.

4. The system of claim 1, wherein said first signing means comprises:

first means for signing said saved vote with said date and said time retrieved from said trusted time source appended thereto with a voter identifier; and

second means for signing said saved vote with said date and said time retrieved from said trusted time source appended thereto with a voting machine identifier.

5. The system of claim 1, wherein said hashing function comprises a cryptographic key.