JRS: A Joint Regulating Scheme for Secretly Shared Content Based on Blockchain

For the sake of privacy, encrypting the content shared on the Internet is becoming popular. However, it brings a nontrivial challenge in regulating the illicit shared content (e.g., viruses, rumors, malicious code, etc.). To deal with it, lots of schemes have been proposed, which mainly rely on a third-party—regulatory authority (RA), to perform auditing, regulating or supervising exclusively. Although these schemes mitigate the problem of illicit shared content, they still suffer from the following two issues. On one hand, relying on a single RA alone may lead to the serious problems of injustice and inadequate regulating. On the other hand, users’ privacy is violated since an independent RA unconditionally inspects all the files shared by users. Therefore, we propose a joint regulating scheme (JRS) for secretly shared content based on threshold secret sharing algorithm and blockchain technology. To make the censor activities democratic and public, they are authorized by both the RAs and blockchain miners during which two threshold secret sharing algorithms are applied. Further, only the suspicious users (or files) are censored and the whole process is recorded as blockchain transactions to balance the user privacy and censoring fairness. At last, the results of security and performance analysis show that JRS can resist the known attacks and the cost is acceptable in practice.