A Derivative Matrix-Based Covert Communication Method in Blockchain

Abstract

The data in the blockchain cannot be tampered with and the users are anonymous, which enables the blockchain to be a natural carrier for covert communication. However, the existing methods of covert communication in blockchain suffer from the predefined channel structure, the capacity of a single transaction is not high, and the fixed transaction behaviors will lower the concealment of the communication channel. Therefore, this paper proposes a derivation matrix-based covert communication method in blockchain. It uses dual-key to derive two types of blockchain addresses and then constructs an address matrix by dividing addresses into multiple layers to make full use of the redundancy of addresses. Subsequently, to solve the problem of the lack of concealment caused by the fixed transaction behaviors, divide the rectangular matrix into square blocks with overlapping regions and then encrypt different blocks sequentially to make the transaction behaviors of the channel addresses match better with those of the real addresses. Further, the linear congruence algorithm is used to generate random sequence, which provides a random order for blocks encryption, and thus enhances the security of the encryption algorithm. Experimental results show that this method can effectively reduce the abnormal transaction behaviors of addresses while ensuring the channel transmission efficiency.

Network Covert Channels

“…Wide access, large capacity covert channels, information concealment and identity anonymity, and resilient communication channels are among the benefits of blockchain technology for covert communication. Zang et al [2] investigated covert channels across several blockchain layers and identified six types of covert channels in contract layer, network layer, data layer, and motivation layer of blockchain. A great medium for covert communication is the blockchain network [28].…”

“…A significant area of study in information concealment is covert communication, which uses hidden routes to send information covertly. When people are communicating covertly, their relationship can be safeguarded and confidential information cannot be reached, detected, or recovered by unauthorized parties [2]. On the other hand, a covert channel provides an open avenue for hackers to spread destructive activity or leak private information without being discovered [3].…”

Strengthening Maqāṣid al-Sharī’ah Values in Halal Traceability: Evidence and Analysis of Block Chain Based on Halal Supply Chain Applications

“…16 If the majority of codes reach a valid signature consensus, a new block of transactions is accepted into the ledger, and the new block is added to the transaction chain. 17 If the majority disapproves of the addition or modification of a ledger entry, it is rejected and not added to the chain. This distributed consensus model is what allows blockchain to run as a distributed ledger without the need for some authority, hence, valid and invalid data can be identified.…”