A Decentralized Secure Mailbox System based on Blockchain

Nowadays, the communication services provided by the e-mail system are used all over the world for formal communication and business negotiation. The traditional e-mail systems provide services based on their centralized servers. If the centralized servers are attacked, the confidential message and the private information will be leaked to the attacker. To this end, this paper uses blockchain technology to build a decentralized e-mail system with trust and accountability. To improve the PBFT algorithm which is widely-used for blockchain consensus and reduce the bad influence brought by the abnormal blockchain nodes, this work proposes a node quality control strategy for blockchain consensus nodes. Moreover, this paper designs the blockchain-based evidence storage module and dispute resolution module to serve our mailbox users. The experiment results show that the blockchain-based e-mail system proposed in this paper can achieve a high-quality consensus mechanism with the node quality control strategy and reduce the transaction delay time.