Value transfer system

• US 6,366,894 B1
• Filed: 02/23/1998
• Issued: 04/02/2002
• Est. Priority Date: 06/30/1995
• Status: Expired due to Term

• Current Assignee: Mondex International Ltd. (MasterCard Incorporated)
• Original Assignee: Mondex International Ltd. (MasterCard Incorporated)
• Inventors: Everett, David Barrington, Viner, John
• Primary Examiner(s): Kemper, Melanie A.
• Application Number:
  US08/973,708
• Time in Patent Office: 1,499 Days
• Field of Search: 380/2, 380/3, 380/4, 380/21, 380/23, 380/28, 380/29, 380/49, 380/277, 902/2, 902/4, 902/26, 235/380, 235/382, 705/1, 705/64, 705/71, 705/76, 705/65, 705/69
• US Class Current: 705/76
• CPC Class Codes: G06Q 20/3552 Downloading or loading of personalisation data
• CPC Class Codes: G06Q 20/382 insuring higher security of transaction
• CPC Class Codes: G06Q 20/3821 Electronic credentials
• CPC Class Codes: G06Q 20/3829 involving key management
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system

Abstract

A value transfer system using integrated circuit cards for exchanging electronic cash in off-line transactions employs cryptographically secure message protocols. Cards are loaded each with two schemes from a series and interaction between cards determines and uses the oldest scheme shared by the cards, causing one card to switch schemes irrevocably if that common scheme is its second scheme. In this way, a switch to a new scheme can migrate through the system.

Claims

1. A value transfer system comprising a multiplicity of electronic programmed microprocessor application carrier devices (ACD'"'"'S) each comprising an electronic purse having a value store, the ACD'"'"'s being adapted to be coupled together in pairs so as to couple the purses and enable value to be exchanged in transactions between the purses, said value exchange being effected by exchanges of messages secured by a cryptographic security scheme, the system further comprising a sequential series of cryptographic security schemes ranging from old to new and each purse being programmed with at least two schemes in said series such that when two purses are coupled in a pair to exchange value between electronic purses, the oldest usable cryptographic security scheme common to both said two purses is identified and used and any cryptographic security scheme of the series in either said two purses which is older than the oldest common scheme is render unusable or, if there is no useable cryptographic security scheme common to both said two purses, the exchange of value is not permitted whereby for first and second purses having useable schemes A and B, where A is older than B, and a third purse having scheme B as its oldest usable scheme, the coupling of said first purse with said second purse results in scheme A being rendered unusable:

1) in said first purse if said second purse is first coupled with said third purse and then coupled with said first purse before being coupled with any other purse, and

2) in said second purse if said first purse is first coupled with said third purse and then coupled with said first purse before being coupled with any other purse.

2. A value transfer system as claimed in claim 1 wherein each purse has a memory region in which is stored an identifier for the cryptographic security scheme currently in use by the purse, the scheme identifiers being exchanged between a coupled pair of purses as a preliminary in a value exchange transaction.

3. A value transfer system as claimed in claim 1 wherein each purse is programmed with two successive cryptographic security schemes in the sequential series.

4. A value transfer system as claimed in claim 1 wherein each cryptographic security scheme comprises at least one cryptographic algorithm and at least one cryptographic key and members of the series differ in respect of their algorithms or their keys.

5. A value transfer system as claimed in claim 1 wherein successive members of the series of cryptographic security schemes are the same except that they are associated with different scheme identifiers, the scheme identifiers being stored in the purses and being used to identify the oldest common cryptographic scheme of a pair of coupled purses and to control the inhibition of any older cryptographic security scheme of the series in either purse.

6. A value transfer system as claimed in claim 1 wherein selected ACD'"'"'s are provided with two electronic purses programmed with respective and different cryptographic security schemes, said selected ACD'"'"'s being programmed, on being coupled to another ACD to select a purse so as to allow a transaction between the purse of the said other ACD and the selected purse according to compatibility of the purse cryptographic security systems.

7. A value transfer system as claimed in claim 2 wherein each purse is programmed with two successive cryptographic security schemes in the sequential series.

8. A value transfer system as claimed in claim 2 wherein each cryptographic security scheme comprises at least one cryptographic algorithm and at least one cryptographic key and members of the series differ in respect of their algorithms or their keys.

9. A value transfer system as claimed in claim 7 wherein each cryptographic security scheme comprises at least one cryptographic algorithm and at least one cryptographic key and members of the series differ in respect of their algorithms or their keys.

10. A value transfer system as claimed in claim 2 wherein successive members of the series of cryptographic security schemes are the same except that they are associated with different scheme identifiers, the scheme identifiers being stored in the purses and being used to identify the oldest common cryptographic scheme of a pair of coupled purses and to control the inhibition of any older cryptographic security scheme of the series in either purse.

11. A value transfer system as claimed in claim 3 wherein successive members of the series of cryptographic security schemes are the same except that they are associated with different scheme identifiers, the scheme identifiers being stored in the purses and being used to identify the oldest common cryptographic scheme of a pair of coupled purses and to control the inhibition of any older cryptographic security scheme of the series in either purse.

12. A value transfer system as claimed in claim 4 wherein successive members of the series of cryptographic security schemes are the same except that they are associated with different scheme identifiers, the scheme identifiers being stored in the purses and being used to identify the oldest common cryptographic scheme of a pair of coupled purses and to control the inhibition of any older cryptographic security scheme of the series in either purse.

13. A value transfer system as claimed in claim 2 wherein selected ACD'"'"'s are provided with two electronic purses programmed with respective and different cryptographic security schemes, said selected ACD'"'"'s being programmed, on being coupled to another ACD to select a purse so as to allow a transaction between the purse of the said other ACD and the selected purse according to compatibility of the purse cryptographic security systems.

14. A value transfer system as claimed in claim 3 wherein selected ACD'"'"'s are provided with two electronic purses programmed with respective and different cryptographic security schemes, said selected ACD'"'"'s being programmed, on being coupled to another ACD to select a purse so as to allow a transaction between the purse of the said other ACD and the selected purse according to compatibility of the purse cryptographic security systems.

15. A value transfer system as claimed in claim 4 wherein selected ACD'"'"'s are provided with two electronic purses programmed with respective and different cryptographic security schemes, said selected ACD'"'"'s being programmed, on being coupled to another ACD to select a purse so as to allow a transaction between the purse of the said other ACD and the selected purse according to compatibility of the purse cryptographic security systems.

16. A value transfer system as claimed in claim 5 wherein selected ACD'"'"'s are provided with two electronic purses programmed with respective and different cryptographic security schemes, said selected ACD'"'"'s being programmed, on being coupled to another ACD to select a purse so as to allow a transaction between the purse of the said other ACD and the selected purse according to compatibility of the purse cryptographic security systems.