A Blockchain-based Covert Document Communication System Model

The communication method in which both parties could modify certain types of shared resources without attracting the attention of other users is called covert communication. Blockchain is an integrated technology system platform that combines cryptography, mathematics, computer programming, game, and other disciplines. Generally, researchers believe that blockchain, as a distributed storage database that can still guarantee security in an unreliable network environment, has excellent characteristics such as open, decentralized, untrusted, anonymous, tamper prevention, traceability, and contract execution automation. More and more studies have applied it to covert communication technology. To satisfy the requirements of increasing confidentiality of information transmission, enhancing the quantity of data transmitted by covert communication, and decreasing the loss of secret information, this paper proposes a covert document communication model based on blockchain. According to the structure of Monero, the sensitive documents are encrypted by attribute-based encryption, and the communication model that can transmit confidential documents is realized by combining an interplanetary file system. The performance of this scheme is experimentally analyzed, and the concealment and security are proven.