System and method for widely witnessed proof of time

• US 20020112157A1
• Filed: 04/26/2001
• Published: 08/15/2002
• Est. Priority Date: 09/22/1997
• Status: Active Grant

• Current Assignee: DFS Linkages, Inc.
• Original Assignee: Proofspace Incorporated
• Inventors: Doyle, Michael D., Bernsohn, Glenn W., Doyle, Paul F., Roberts, Jeffrey D., Goetze, Stephen P., Wolf, Kirk James
• Granted Patent: US 7,047,415 B2
• Time in Patent Office: Days
• US Class Current: 713/157
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32
• CPC Class Codes: H04L 9/007 involving hierarchical structures
• CPC Class Codes: H04L 9/3265 using certificate chains, trees or paths; Hierarchical trust model
• CPC Class Codes: H04L 9/3297 involving time stamps, e.g. generation of time stamps

Abstract

A system for authenticating records without reliance upon a trusted third party. A first server provides a sequential series of certifications associated with discreet, non-overlapping time Intervals. The server can provide selected information to a second server which, in turn, incorporates the request and associated information in a cross-certification. The cross-certification is then provided to more other servers. Accordingly, a “chain-mail” of certifications among a variety of servers is provided. The system thus provides effective protection against a breach of security in any one server, resulting in increased reliability in the authentication of records.

Claims

1. A method for providing security with respect to who provided digital data at what time, said method comprising the steps of:

performing a serially chained certification process including;

(a) forming a first interval certification at a first server including the server'"'"'s identification, the start time of an interval chain in UTC, the start time of the interval in UTC, the stop time of the interval, a public key for the interval, a digital signature for the interval, signed by a previous interval'"'"'s private key, and a digital signature for the interval, signed by the interval'"'"'s private key;

(b) upon expiration of the first interval, destroying its private key;

(c) configuring a second server to request a cross-certification for a second interval so that the first server is effectively requested to provide independent proof of the existence of the interval (and its public key) at a point in time witnessed by the first server;

(d) continuing steps (a), (b), and (c) for second, third, and following intervals so that intervals are cross-chained with other servers to form a widely witnessed, temporal web of signed intervals of time.