Blockchain for Secure Communication

Blockchain technology, originally associated with digital currencies, possesses key features such as decentralization, anonymity, robustness, and resistance to tampering, making it an ideal platform for building covert communication channels. This chapter begins by introducing the concept of network covert channels, discussing their definition, historical development, and the architecture of blockchain technology with an exploration of traditional network covert channels. It then highlights the advantages of blockchain-based covert communication channels over conventional methods. The chapter classifies blockchain network covert channels based on several key components. It provides a detailed analysis of the advantages and disadvantages of these channels in terms of covert nature, transmission efficiency, and communication costs. Finally, the chapter addresses existing challenges and limitations within blockchain network covert channels and offers insights into future research directions to improve their efficiency, security, and scalability in the context of secure communication.