Data card verification system

• US 20020174339A1
• Filed: 07/01/2002
• Published: 11/21/2002
• 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 7,472,276 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
• 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 method of verifying a pair of correspondents in electronic transaction said correspondents each including a first and second signature schemes said method comprising the steps of:

said first correspondent signing information according to said first signature scheme and transmitting said first signature to said second correspondent;

said second correspondent verifying said first signature received from said first correspondent, wherein said verification is performed according to said first signature scheme;

said second correspondent signing information according to a second signature scheme and transmitting said second signature to said first correspondent;

said first correspondent verifying said second signature received from said second correspondent, wherein said verification is performed according to said second signature algorithm; and

said transaction being rejected if either verification fails.

2. A method as defined in claim 1, 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 method as defined in claim 1, said first digital signature scheme being an RSA type scheme and said second signature scheme being an elliptic curve type scheme.

4. A method as defined in claim 1, said first digital signature scheme being a DSS type scheme and said second signature scheme being an elliptic curve type scheme.

5. A method of verifying a pair of correspondents in electronic transaction, said correspondents each including a first and second signature scheme, said method comprising the steps of:

said first correspondent transmitting to said second correspondent, a certificate including public key and identification information of said first correspondent;

said second correspondent verifying said certificate and extracting said public key and identification information therefrom;

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

said first correspondent signing said received challenge R₁ in accordance with said first signature scheme;

said first correspondent generating a second challenge and transmitting said second challenge along with said signature C2 to said second correspondent;

said second correspondent verifying said signature C2 in accordance with said first signature scheme;

said second correspondent signing said second challenge R2 in accordance with said second signature scheme and transmitting said second signature to said first correspondent; and

said first correspondent verifying said second signature in accordance with said second signature scheme, whereby said transaction is rejected if either said first signature or said second signature is not verified.

6. A smart card for use in an electronic transaction, with a second correspondent, said card comprising:

a memory including

a first signature scheme consisting of a first signature generation algorithm and an associated verification algorithm;

a second signature scheme consisting of a second signature generation algorithm and an associated verification algorithm;

a program for invoking said algorithms; and

processor means for running said first verification algorithm for verifying first information received from said second correspondent and for running said second signature algorithm for signing a second information for transmission to said second correspondent.