Trusted Execution Environments for Blockchain: Toward Robust, Private, and Scalable Distributed Ledgers

Blockchain technology presents significant security challenges despite its transformative impact on digital transactions and decentralized data management. Key vulnerabilities include insecure smart contract execution, data privacy risks on transparent ledgers, and susceptibility of certain consensus mechanisms to attacks. trusted execution environments (TEEs) offer a robust hardware-based solution to these critical issues. By providing isolated execution spaces, TEEs safeguard code and data confidentiality and integrity, thereby fundamentally strengthening blockchain security. This article presents a comprehensive analysis of TEEs in blockchain technology. First, we analyze the challenges inherent in blockchain systems and demonstrate the advantages of TEEs over current methods. A detailed analysis of TEE properties, variants, and evolution in the blockchain field is provided. Additionally, we explore innovative TEE-based solutions across three key application domains: 1) consensus mechanism optimization; 2) confidential computation and execution; and 3) payment networks and financial applications. Furthermore, we propose a research agenda addressing current challenges, such as vulnerabilities to side-channel attacks and dependencies on hardware trust assumptions. Finally, we propose five critical directions for future TEE–blockchain integration: 1) enhancement of security and privacy protection with particular attention to the trusted computing base (TCB) minimization; 2) performance optimization through hardware architecture advancement; 3) trust model refinement to reduce centralization; 4) expansion of application scenarios through interdisciplinary collaboration; and 5) development of cross-chain interoperability standards. Our work contributes to blockchain security knowledge and provides a roadmap for researchers and practitioners in this rapidly evolving field.