Method and device for the generation of checkable forgery-proof documents

• US 20050226422A1
• Filed: 03/10/2003
• Published: 10/13/2005
• Est. Priority Date: 03/13/2002
• Status: Active Grant

• Current Assignee: Deutsche Post AG
• Original Assignee: Deutsche Post AG
• Inventors: Meyer, Bernd, Lang, Jurgen
• Granted Patent: US 7,409,062 B2
• Time in Patent Office: Days
• US Class Current: 380/277
• CPC Class Codes: G07B 17/00733 Cryptography or similar special procedures in a franking system
• CPC Class Codes: G07B 2017/00766 Digital signature, e.g. DSA, DSS, ECDSA, ESIGN
• CPC Class Codes: G07B 2017/00959 Cryptographic modules, e.g. a PC encryption board

Abstract

The invention relates to a method and a device for the generation of checkable forgery-proof documents with an externally supplied cryptographic module, whereby the checking of authenticity of the document is carried out without using key information belonging to the cryptographic module. According to the invention, the method and the device are characterised in that the cryptographic module is supplied with two types of data, even on supply from a communication partner which is cryptographically not trustworthy, which either remain in the cryptographic module or are attached to the document. The information remaining in the cryptographic module is used to secure the document information by means of a check value and the information transferred into the document serves to verify the securing of the document by the cryptographic module during a check of the authenticity of the document at a checkpoint.

Claims

1. A method for the generation of forgery-proof documents or data records, whereby key information is generated and whereby encrypted checking information is formed from the key information and from a transaction indicator,

comprising the steps of

generating random key information and the formation of the forming encrypted checking information from the key information and from a transaction indicator in a cryptographically reliable contact station,

encrypting the key information in the cryptographically reliable contact station,

transmitting the encrypted checking information and the encrypted key information by the cryptographically reliable contact station to an intermediate station,

the intermediate station temporarily storing the encrypted key information and the encrypted checking information and subsequently transmitting this to a cryptographic module of a document producer at a different point in time from the transfer between the cryptographically reliable contact station and the intermediate station.

2. The method according to claim 1,

comprising generating

the key information in such a way that the key information is formed randomly.

3. The method according to

claim 1, comprising configuring at least one of

the encrypted key information and the encrypted checking information is in such a way that it cannot be decrypted in the intermediate station.

4. The method according to

claim 1, comprising

the cryptographic module decrypting the key information with a key contained in the cryptographic module.

5. The method according to

claim 1, comprising

the document producer entering his own data into the cryptographic module.

6. The method according to

claim 1, comprising irreversibly linking

the data entered by the document producer to the key information by means of the cryptographic module.

7. The method according to claim 6,

comprising irreversibly linking

the data entered by the document producer and the decrypted key information by using the key information to form a check value for the document.

8. The method according to claim 6

comprising forming at least one of a document and a data record from

the result of the irreversible linking of the data entered by the document producer with the decrypted key information and transmitting the document or data record to a checking station.

9. The method according to claim 8,

wherein

the document or data record transmitted to the checking station contains the document producer'"'"'s own data, at least partially in plain text.

10. The method according to claim 8

comprising entering

the encrypted checking information into the document or data record that is transmitted to the checking station.

11. The method according to

claim 1 comprising encrypting

information remaining in the cryptographic module in such a way that it can be decrypted in the cryptographic module.

12. The method according to

claim 1, supplying

the cryptographic module with the information, also in case of a supply via communication partners that are not reliable in the cryptographic sense, by a cryptographically reliable station whose information can be relied on by the checking station.

13. The method according to claim 12,

in order for a reliable station to provide reliable information for the cryptographic module, using cryptographic encryptions that the checking station can reverse.

14. The method according to

claim 1 comprising supplying

the cryptographic module via communication partners that are cryptographically non-reliable in such a way that the information is forwarded to the cryptographic module at a different point in time.

15. The method according to claim 1

comprising supplying

of the cryptographic module via communication partners that are cryptographically not reliable is carried out in such a way that an exchange of information within a dialog is not necessary.

16. The method according to claim 1

comprising cryptographically linking

the two types of data to each other, such that said linking cannot be discovered by means of crypto-analysis.

17. The method according to claim 19,

wherein

the cryptographic linking of the two types of data is such that non-linear fractions are added that are known only to the reliable contact station and to the checking station.

18. The method according to

claim 1, wherein.

the generated forgery-proof documents or data records contain monetary value information.

19. The method according to claim 18,

comprising cryptographically connecting

the monetary value information to the document or data record in such a way that a check value can be formed by comparing the monetary value information to the document or data record.

20. The method according to claim 18

wherein

the monetary value information contains proof of the payment of postage amounts.

21. The method according to claim 20,

comprising linking

the monetary value information that proves the payment of postage amounts to identification data of the document producer.

22. The method according to claim 20

comprising linking

the monetary value information to address data.

23. A value transfer center with an interface for loading monetary values,

comprising an interface to receive encrypted information of a cryptographically reliable contact station and to temporarily store the received encrypted information as well as means for receiving value transfer requests by at least one cryptographic module and of forwarding the received encrypted information to the cryptographic module at a different point in time.

24. The value transfer center according to claim 23,

wherein

the information is encrypted in such a way that it cannot be decrypted in the value transfer center.