A covert communication model of Ethereum based on smart contracts

To solve the problems of low hidden capacity, weak concealment and low transmission efficiency in the existing blockchain covert communication, a covert communication model of Ethereum based on smart contracts is proposed. First, the sender processes the plaintext information and the key information into a binary sequence, to get the secret information to be embedded. The sender embeds the secret information into the smart contract source code by using the space method. Secondly, the sender compiles and deploys the smart contract containing the secret information to the Ethereum network. Finally, the receiver can use the pre-shared account information and key to restore the plaintext information to the acquired smart contract through the inverse process of the embedding algorithm. Through the deployment experiment of the Ethereum test network, the results show that the model realizes covert communication based on smart contract information hiding. By analysing and comparing the existing similar models, the model further improves the hidden capacity, reduces the communication cost, has better performance concealment and security.