A blockchain-based quantum-secure reporting protocol

The reporting systems are needed to design so that the whistleblower’s privacy, report confidentiality, and report integrity should be under-consideration. Additionally, it is expected that the approved report will be accessible publicly and not changed. We believe that blockchain technology is the best choice for reporting systems’ infrastructure since it provides a transparent and immutable database. This paper presents the first blockchain-based quantum-secure reporting protocol (QS-RP) using multivariate public key cryptography (MPKC). In the QS-RP, a fast verification mechanism is applied, which makes use of the Merkle technique. The QS-RP provides confidentiality to the selectively secure multi-key (C-SSMK) and unforgeability to selectively secure multi-key (UF-SSMK). Additionally, the QS-RP provides several new features such as report confidentiality before report generation, user/whistleblower privacy, and report integrity. The most important feature of the QS-RP is providing the whistleblower’s privacy and report confidentiality against quantum computers. Analysis of the security of the QS-RP indicated the mentioned claims in the random oracle model (ROM). Finally, the QS-RP is compared with other blockchain-based reporting protocols. The comparison shows the QS-RP provides more security features than other reporting protocols, and the performance analysis’s results show that it is 90 % faster in the execution time on the user side, and it is 66 % efficient in the communication overhead in compared to other blockchain-based reporting protocols. Moreover, the QS-RP has no on-chain overhead for whistleblowers.