免共谋公钥叛逆者追踪方案

Collusion-free public-key traitor tracing scheme

当参与共谋的叛逆者不超过某个预先给定的范围时,现有的叛逆者追踪方案都可以追踪出至少一个叛逆者,但是如何阻止共谋的发生还是一个有待解决的问题。提出一种新的叛逆者追踪方案,方案中不同用户间的解密钥是不相关的,这样无论多少个用户都不能通过共谋构造出一个解密钥来,并且能快速准确地追踪出叛逆者,对潜在的不良用户有更好的威慑作用。与现有方案相比,本方案具有更高的传输效率。

All the existing traitor tracing schemes can trace at least a traitor when the number of traitors is not beyond a certain predefined value. However, how to prevent traitors from colluding a valid key is a open problem. A new traitor tracing scheme was presented, in which traitors can not get a valid key by conspiracy, no matter how many traitors there were because each user＇s decryption key was independent of any others. Further, our scheme can determine a traitor in speediness and accuracy, thus it can reach a better determent to those potential bad users. Meanwhile, compared with present schemes, this scheme has a higher transmission efficiency.