Method for certifying and authentifying security documents based on a measure of the relative variations of the different processes involved in its manufacture

• US 9,871,660 B2
• Filed: 12/23/2014
• Issued: 01/16/2018
• Est. Priority Date: 12/23/2014
• Status: Active Grant

• Current Assignee: Banco De Mã©Xico (Gobierno Federal De Los Estados Unidos Mexicanos)
• Original Assignee: Banco De Mã©Xico (Gobierno Federal De Los Estados Unidos Mexicanos)
• Inventors: Terborg Del Rosal, Heinrich Fidencio, Gonzalez Candela, Ernesto, Lopez Gonzalez, Monica
• Primary Examiner(s): Poltorak, Peter
• Application Number:
  US14/581,984
• Publication Number:
  US 20160182239A1
• Time in Patent Office: 1,120 Days
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07D 7/12 Visible light, infrared or ultraviolet radiation
• CPC Class Codes: G07D 7/2033 Matching unique patterns, i.e. patterns that are unique to each individual paper
• CPC Class Codes: H04L 9/3236 using cryptographic hash functions
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823
• CPC Class Codes: H04L 9/3268 using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]
• CPC Class Codes: H04N 1/32149 Methods relating to embedding, encoding, decoding, detection or retrieval operations
• CPC Class Codes: H04N 1/32299 using more than one embedding method
• CPC Class Codes: H04N 1/32304 Embedding different sets of additional information
• CPC Class Codes: H04N 1/32352 Controlling detectability or arrangements to facilitate detection or retrieval of the embedded information, e.g. using markers for decoding, detection or retrieval operations H04N1/32149 and subgroups take precedence

Abstract

Methods for certifying a security document comprising the steps of: a) selecting a set of unique characteristics, obtained as the result of the variations in the manufacturing process and supplies, b) getting a digital image of a security document and obtaining data of the relative position between features selected from different manufacturing processes (register), c) constructing a message by measuring the register of selected features from the document and the document ID data, d) constructing a hashed message, the hashed message being the message obtained after being encoded by means of a unidirectional cryptographic hash function, e) encrypting the hashed message using a public key cryptographic system to obtain a digital certificate by means of a private key, and f) storing the digital certificate in an external database.

Claims

1. A computer-implemented method for certifying a security document, comprising:

providing a security document which is the result of a plurality of independent manufacturing processes that provide each an image, said security document having thus a set of unique characteristics related to the use of different supplies for manufacturing the security document;

obtaining, via the one or more processors, a digital image of the security document;

selecting, via one or more processors, a determined set of locations in images of each of the plurality of different manufacturing processes in the document image;

determining a reference location in an image of a manufacturing process of the plurality of different manufacturing processes;

calculating relative positions (register data) of a location within the determined set of locations in images of each of the different manufacturing processes with respect to the reference location;

constructing, via the one or more processors, a message from said register data measured from the determined set of locations of the document image;

constructing, via the one or more processors, a hashed message, wherein the hashed message is obtained by encoding the message with a unidirectional cryptographic hash function;

encrypting, via the one or more processors, the hashed message using a private key, by a public key cryptographic system, to obtain a digital certificate;

visibly printing the digital certificate on the security document; and

storing, via the one or more processors, the digital certificate in an external database.

2. The method for certification according to claim 1 wherein the digital image is taken with light with a wavelength between 200 and 1500 nanometers.

3. The method for certification according to claim 1 wherein the digital image is taken with visible light.

4. The method for certification according to claim 1 wherein many parts of the same document are independently certified.

5. A method for certification according to claim 1, wherein the security document is a banknote, a check, a passport, visa, ID document or birth certificate.

6. The method for certifying a security document according to claim 1, wherein the register data is obtained throughout the production line.

7. The method for certifying a security document according to claim 1, wherein the register data is obtained during quality inspection.