A fair distribution scheme for joint fingerprinting and decryption methods= Sprawiedliwy schemat dystrybucji dla metod łącznego osadzania odcisku palca oraz deszyfracji

Abstract

The paper addresses the fairness of the security provided by digital fingerprinting methods. It was noted that the digital fingerprinting techniques are designed primarily to protect service providers against the actions of malicious users, while honest users remain vulnerable to acts of malicious providers. The paper describes the customer's rights problem and the unbinding problem, which also apply to joint fingerprinting and decryption methods. The author proposes a solution to these problems in the form of fair distribution scheme for joint fingerprinting and decryption methods. The proposed scheme is fair, because it provides the expected protection from the perspective of both the provider and the customer. Mutual authentication is realized using certificates and digital signatures. The scheme does not require that the customer contact with any other party than the seller and, simultaneously, does not require cooperation with the customer during the identification of malicious users.