METHOD AND SYSTEM FOR PRESERVING PRIVACY AND ACCOUNTABILITY

• US 20140304519A1
• Filed: 11/07/2012
• Published: 10/09/2014
• Est. Priority Date: 11/08/2011
• Status: Active Grant

• Current Assignee: AGT International GMBH
• Original Assignee: Ats Group (Ip Holdings) Limited
• Inventors: Gorecki, Christian, Zeiger, Florian
• Granted Patent: US 9,344,285 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: G06Q 20/383 Anonymous user system
• CPC Class Codes: H04L 2209/42 Anonymization, e.g. involving pseudonyms
• CPC Class Codes: H04L 2209/72 Signcrypting, i.e. digital signing and encrypting simultaneously
• CPC Class Codes: H04L 2463/062 applying encryption of the keys cryptographic mechanisms or cryptographic arrangements for key distribution using key encryption key H04L9/0822
• CPC Class Codes: H04L 63/0421 Anonymous communication, i.e. the party's identifiers are hidden from the other party or parties, e.g. using an anonymizer
• CPC Class Codes: H04L 63/045 wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption cryptographic mechanisms or cryptographic arrangements using a plurality of keys or algorithms H04L9/14
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 9/0825 using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

A computer implemented method, computer program product, server and clients for preserving privacy and accountability. The server receives from a first client computer pseudonymous, encrypted data and stores the pseudonymous, encrypted data. The -server further receives receiving at from a second client computer a data request for the pseudonymous, encrypted data and provides the pseudonymous, encrypted data to the second client computer in response to the data request. The server receives from the second client computer a signed key request for at least one key, wherein the at least one key is configured to decrypt the pseudonymous, encrypted data and wherein the signed key request comprises a public key of the second client computer. The server receives from the first client computer the at least one key, wherein the at least one key is encrypted with the public key of the second client computer and provides the at least one encrypted key to the second client computer in response to the signed key request.

Claims

1. A computer implemented method (4000) on a server computer (1001) for preserving privacy and accountability, comprising:

receiving (4100) from a first client computer (1002) pseudonymous, encrypted data (1101);

storing (4200) the pseudonymous, encrypted data (1101) at the server computer (1001);

receiving (4300) from a second client computer (1003) a data request (1202) for the pseudonymous, encrypted data (1101);

providing (4400) the pseudonymous, encrypted data (1101) to the second client computer (1003) in response (1203) to the data request;

receiving (4500) from the second client computer (1003) a signed key request (1204) for at least one key (1301), wherein the at least one key (1301) to be configured to decrypt the pseudonymous, encrypted data (1101) and wherein the signed key request (1204) comprises a public key (1303-pu) of the second client computer (1003);

receiving (4600) from the first client computer (1002) the at least one key, wherein the at least one key (1301) is encrypted with the public key (1303-pu) of the second client computer (1003); and

providing (4700) the encrypted at least one key to the second client computer (1003) in response to the signed key request.

2. The method (4000) of claim 1, further comprising:

receiving (4810) from the second client computer (1003) signed, encrypted transaction data (1102), wherein the transaction data is encrypted with a public key (1302-pu) of the first client computer (1002);

storing (4820) the signed, encrypted transaction data (1102) at the server computer (1001); and

providing (4830) the signed, encrypted transaction data (1102) to the first client computer (1002) on request of the first client computer (1002).

3. The method (4000) of claim 2, wherein the transaction data (1102) comprises a transaction number and a transaction value:

4. The method (4000) of claim 2 or 3, wherein the first client computer (1002) is configured to decrypt the signed, encrypted transaction data (1102) using a private key (1302-pr) which is related to the public key (1302-pu) of the first client computer (1002).

5. The method (4000) of anyone of the claims 2 to 4, wherein the first client computer (1002) is configured to request (4840) a reimbursement from a reimbursement entity (1004) in accordance with the decrypted transaction data (1102a).

6. The method (4000) of anyone of the previous claims, wherein the second client computer is configured to decrypt the at least one encrypted key (1301) by using a private key (1303-pr) which is related to the public key (1303-pu) of the second client computer (1003), and is further configured to decrypt the pseudonymous, encrypted data (1101) by using the at least one decrypted key (1301a).

7. The method (4000) of anyone of the previous claims, wherein the second client computer (1003) requests and receives further pseudonymous, encrypted data provided by the first client computer (1002) while still using the already decrypted at least one key (1301a).

8. The method (4000) of anyone of the previous claims, wherein the at least one key (1301) becomes invalid after a predefined validity interval.

9. The method (4000) of anyone of the claims 1 to 7, wherein the at least one key (1301) becomes invalid upon an invalidation action of the first client computer (1002).

10. The method (4000) of anyone of the previous claims, wherein the pseudonymous, encrypted data (1101) comprises a plurality of data sets (1101-1, 1101-2, 1101-3, 1101-n), each data set (1101-1, 1101-2, 1101-3, 1101-n) being encrypted with a separate key (1301-1, 1301-2, 1301-3, 1301-n).

11. The method (4000) of claim 10, wherein the second client computer (1003) receives only a subset of the plurality of separate keys.

12. The method (4000) of anyone of the previous claims, wherein the pseudonymous, encrypted data (1101) is associated with non-encrypted data (1101-0), wherein the non-encrypted data (1101-0) is configured to categorize or classify the pseudonymous, encrypted data (1101).

13. The method (4000) of anyone of the previous claims, wherein the server computer (1001) is a non-trusted server computer.

14. A computer program product that when loaded into a memory of a computing device and executed by at least one processor of the computing device executes the steps of the computer implemented method according to of anyone of the claims 1 to 13.

15. A server computer (1001) comprising:

an interface component (1011) configured;

to receive (4100) from a first client computer (1002) pseudonymous, encrypted data (1101) and further;

to receive (4300) from a second client computer (1003) a data request (1202) for the pseudonymous, encrypted data (1101);

to provide (4400) the pseudonymous, encrypted data (1101) to the second client computer (1003) in response (1203) to the data request (1202);

to receive (4500) from the second client computer (1003) a signed key request (1204) for at least one key (1301), wherein the at least one key (1301) is to be configured to decrypt the pseudonymous, encrypted data (1101) and wherein the signed key request (1204) comprises a public key (1303-pu) of the second client computer (1003);

to receive (4600) from the first client computer (1002) the at least one key (1301), wherein the at least one key (1301) is encrypted with the public key (1303-pu) of the second client computer (1003); and

to provide (4700) the at least one encrypted key (1301) to the second client computer (1003) in response (1206) to the signed key request (1204);

and

a data storage (1031) component configured to store (4200) the pseudonymous, encrypted data (1101) at the server computer (1001).

16. The server computer (1001) of claim 15, wherein:

the interface component (1011) is further configured;

to receive (4810) from the second client computer (1003) signed, encrypted transaction data (1102), wherein the transaction data is encrypted with a public key (1302-pu) of the first client computer (1002); and

to provide (4830) the signed, encrypted transaction data (1102) to the first client computer (1002);

and

the data storage component (1031) is further configured to store (4820) the signed, encrypted transaction data (1102) at the server computer (1001).

17. A data consumer client computer (1003), comprising:

an interface component (1013) configured;

to send a data request (1202) for pseudonymous, encrypted data (1101) to a server computer (1001), wherein the pseudonymous, encrypted data (1101) originate from a data producer client computer (1002);

to receive in response (1203) to the data request (1202) the pseudonymous, encrypted data (1101) from the server computer (1001);

to send a signed key request (1204) for at least one key (1301), wherein the at least one key (1301) is to be configured to decrypt the pseudonymous, encrypted data (1101) and wherein the signed key request (1204) comprises a public key (1303-pu) of the data consumer client computer (1003);

to receive in response (1206) to the signed key request (1204) the at least one key (1301) from the server computer, wherein the at least one key is encrypted with the public key (1303-pu) of the data consumer client computer (1003);

and

a data processing component (1023) configured;

to decrypt the at least one encrypted key (1301) by using a private key (1303-pr) which is related to the public key (1303-pu) of the data consumer client computer; and

to decrypt the pseudonymous, encrypted data (1101) by using the at least one decrypted key (1301a).

18. The data consumer client computer (1003) of claim 17, wherein:

the interface component (1013) is further configured;

to send signed, encrypted transaction data (1102) to the server (1001); and

the data processing component (1023) is further configured;

to encrypt the transaction data with a public key (1302-pu) of the data producer client computer (1002).

19. A data producer client computer (1002), comprising:

an interface component (1012) configured;

to send pseudonymous, encrypted data (1001) to a server computer (1001);

to receive from the server computer (1001) a signed key request for at least one key (1301), wherein the at least one key (1301) is to be configured to decrypt the pseudonymous, encrypted data (1101) and wherein the signed key request comprises a public key (1303-pu) of a data consumer client computer (1003); and

to send the at least one key (1301) to the server computer (1001), wherein the at least one key (1301) is encrypted with the public key (1303-pu) of the data consumer client computer (1003);

and

a data processing component (1022) configured;

to encrypt the at least one key with the public key (1303-pu) of the data consumer client computer (1003).

20. The data producer client computer of claim 19, wherein:

the interface component (1012) is further configured;

to receive from the server computer (1001) encrypted transaction data (1102), wherein the transaction data (1102) is encrypted with a public key (1302-pu) of the data producer client computer (1002) and wherein the transaction data (1102) is signed by the data consumer client computer (1003); and

the data processing component (1022) is further configured to decrypt the signed, encrypted transaction data (1102) using a private key (1302-pr) which is related to the public key (1302-pu) of the data producer client computer (1002).

21. The data producer client computer of claim 20, wherein:

the interface component (1012) is further configured to request (4840) a reimbursement from a reimbursement entity (1004) in accordance with the decrypted transaction data (1102a).