DATA CARD VERIFICATION SYSTEM

• US 20090164792A1
• Filed: 11/26/2008
• Published: 06/25/2009
• Est. Priority Date: 02/03/1997
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Scott A. Vanstone
• Inventors: Vanstone, Scott A.
• Granted Patent: US 7,822,987 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/3674 involving authentication
• CPC Class Codes: G06Q 20/3825 Use of electronic signatures
• CPC Class Codes: G06Q 20/401 Transaction verification
• CPC Class Codes: G06Q 20/40975 using encryption therefor
• CPC Class Codes: G06Q 2220/00 Business processing using cryptography postage metering system using cryptography G06Q2250/05
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G07F 7/1016 Devices or methods for securing the PIN and other transaction-data, e.g. by encryption arrangements for secret communication, see H04L9/00
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 9/3066 involving algebraic varieties, e.g. elliptic or hyper-elliptic curves
• CPC Class Codes: H04L 9/3249 using RSA or related signature schemes, e.g. Rabin scheme
• CPC Class Codes: H04L 9/3252 using DSA or related signature schemes, e.g. elliptic based signatures, ElGamal or Schnorr schemes

Abstract

A method of verifying a pair of correspondents in electronic transaction, the correspondents each including first and second signature schemes and wherein the first signature scheme is computationally more difficult in signing than verifying and the second signature scheme is computationally more difficult in verifying than signing. The method comprises the step of the first correspondent signing information according to the first signature scheme and transmitting the first signature to the second correspondent, the second correspondent verifying the first signature received from the first correspondent, wherein the verification is performed according to the first signature scheme. The second correspondent then signs information according to the second signature scheme and transmits the second signature to the first correspondent, the first correspondent verifies the second signature received from the second correspondent, wherein the verification is performed according to the second signature algorithm; the transaction is rejected if either verification fails. The method thereby allows one of the correspondents to participate with relatively little computing power while maintaining security of the transaction.

Claims

1. A computer readable medium comprising computer executable instructions for verifying the authenticity of messages exchanged between a pair of correspondents in an electronic transaction conducted over a data transmission system, said correspondents each including respective signing and verifying portions of a first signature scheme and a second signature scheme different to said first scheme and utilizing an elliptic curve cryptosystem, said computer executable instructions comprising instructions for a first of said correspondents:

obtaining a first signed message from a second of said correspondents, said first signed message having been generated by one of said first and second correspondents signing a message according to a signing portion of one of said signature schemes associated with said one of said first and second correspondents;

utilizing said verifying portion of said one signature scheme to verify said first signed message;

signing a message by utilizing said signing portion of the other of said signature schemes to provide a second signed message;

sending said second signed message to said second of said correspondents to enable said second of said correspondents to verify said second signed message by utilizing said verification portion of said other of said signature schemes; and

rejecting said transaction if either verification fails;

wherein one of said signed messages and verification of one of said signed messages is performed according to said second signature scheme utilizing an elliptic curve cryptosystem.

2. A computer readable medium according to claim 1, wherein said first signature scheme is computationally more difficult in signing than verifying, while said second signature scheme is computationally more difficult in verifying than signing, thereby allowing one of said correspondents to participate with relatively little computing power while maintaining security of said transaction.

3. A computer readable medium according to claim 1, wherein said first digital signature scheme is an RSA type scheme.

4. A computer readable medium according to claim 1, wherein said first digital signature scheme is a DSS type scheme.

5. A computer readable medium comprising computer executable instructions for verifying the authenticity of messages exchanged between a pair of correspondents in electronic transaction conducted over a data transmission system, said correspondents each including respective signing and verifying portions of a first signature scheme and a second signature scheme, different from said first scheme and utilizing an elliptic curve cryptosystem, said computer executable instructions comprising instructions for a first of said correspondents:

obtaining a first certificate C1 including a public key and identification information of a second correspondent from one of said first and second correspondents;

verifying said first certificate C1 and extracting said public key said identification information therefrom;

generating a first challenge R1 and transmitting said challenge R1 to said second correspondent;

receiving from said second correspondent, a second challenge R2 generated by said second correspondent and a second certificate C2, said second certificate C2 having been generated by signing said first challenge R1 in accordance with said signing portion of one of said signature schemes;

verifying said second certificate C2 in accordance with said verification portion of said one of said signature schemes;

signing said second challenge R2 in accordance with said signing portion of the other of said signature schemes to provide a third certificate;

sending said third certificate to said second correspondent to enable said second correspondent to verify said third certificate in accordance with said verification portion of said other of said signature schemes; and

rejecting said transaction if verification of either signature fails.