Protection system for intelligent cards
First Claim
1. A system for allowing authorized users of portable intelligent cards to effect transactions via at least one transaction terminal comprising a plurality of user intelligent cards each having stored therein a code which is the encryption of a combination of a password associated with the respective user and a reference text which is common to all users, the codes stored in all of said cards having been encrypted with the same private key which is associated with the public key of a public-key cryptosystem pair;
- and at least one transaction terminal having means for allowing a card user to inut a password, and means for controlling (1) the retrieval of the code stored in an inserted card, (2) the decryption of the retrieved code with the use of said public key to derive a password part and a text part, (3) the comparisons of the derived password part with the inputted password, and the text part with said common reference text, and (4) the effecting of a transaction only if both of said comparisons are successful.
1 Assignment
0 Petitions
Accused Products
Abstract
There is disclosed a protection system for intelligent cards. Each card has stored in it a code which is the encryption of a concatenation of a user secret password and a common reference text. The encryption is derived by an initialization terminal which uses the private key associated with the public key of a public-key cryptosystem key pair. Each transaction terminal with which a card is used decrypts the stored code in accordance with the public key. A transaction is effected only if the stored code decrypts into the user password which is inputted on a keyboard and the common reference text.
498 Citations
19 Claims
-
1. A system for allowing authorized users of portable intelligent cards to effect transactions via at least one transaction terminal comprising a plurality of user intelligent cards each having stored therein a code which is the encryption of a combination of a password associated with the respective user and a reference text which is common to all users, the codes stored in all of said cards having been encrypted with the same private key which is associated with the public key of a public-key cryptosystem pair;
- and at least one transaction terminal having means for allowing a card user to inut a password, and means for controlling (1) the retrieval of the code stored in an inserted card, (2) the decryption of the retrieved code with the use of said public key to derive a password part and a text part, (3) the comparisons of the derived password part with the inputted password, and the text part with said common reference text, and (4) the effecting of a transaction only if both of said comparisons are successful.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
- 10. A terminal for initializing portable intelligent cards to be used with at least one transaction terminal, each intelligent card having a memory therein, comprising means for assigning a password to a user whose card is to be initialized, means for deriving a code which is the encryption of a combination of the assigned password and a reference text which is common to all users, the code for each user being derived with use of the same private key which is associated with the public key of a public-key cryptosystem pair, and means for controlling the storage in a user card of the respective derived code.
- 12. A portable intelligent card for use in effecting transactions via at least one transaction terminal comprising a housing, a memory within said housing for storing a code, said code being the encryption of a combination of a password associated with the respective card user and a reference text which is common to all other users of like cards, said code having been encrypted with the private key which is associated with the public key of a public key cryptosystem pair, and means for allowing said stored code to be accessed externally of the card.
Specification