A Novel Covert Communication Method Based on Bitcoin Transaction

With the global promotion and application of 5G technology, the data transmitted on the network show explosive growth, and the secure sharing of its important data is still one of the research hotspots. Steganography embeds the data that needs to be shared into digital carrier files and transmits it through open channels, which has important applications in protecting data sharing and realizing covert communication. However, the encrypted files generated by traditional steganography are susceptible to compression, cropping, geometric attacks, and man-made destruction in the process of open channel transmission, resulting in data loss, making it difficult for the receiver to correctly extract secret message. Currently, covert communication on blockchain can solve the above problems, but it also brings some new problems such as high computational complexity, low transmission efficiency, and nondetection resistance. Therefore, in this article, a covert communication method based on Bitcoin transactions is proposed. The proposed method first designs the index matrix of the transaction address. Then, the address interaction relationship that carries the secret message through the transaction index matrix is constructed. Finally, the address interaction relationship that carries the secret message is combined with the transaction amount to complete the covert transmission of the secret message on the blockchain environment. The proposed method improves the security and embedding efficiency of covert communication, reduces the number of transactions, and ensures the integrity of extracting secret message. A series of experimental results show that under the condition of ensuring the necessary security, the proposed method retains the strong robustness of the existing blockchain steganography and has strong resistance to detection.