Concluding Remarks

Abstract

This chapter summarizes all enumerated works to derive some empirical knowledge and generalizes some open problems as future challenges. This chapter concludes as follows: (1). The practical design and analysis of cryptographic schemes for blockchain can address significant problems in blockchain at the algorithmic level. This type of research has received popularity from both global cryptographic community and blockchain developer&s;s community. This research field is the most fast-developing region of all research areas. (2). The intrinsic deficiencies in some traditional cryptographic primitives, like ring signature, IND-CCA2 secure encryption, zero knowledge, etc, prevent the successful application of these primitives in the blockchain. However, tremendous efforts are being made to make these primitives practical and applicable by researchers. Hopefully, we can derive efficient and practically-secure zk-SNARKs or public key schemes as building blocks or overlays for blockchain in the near future.} (3) The formal and rigorous design and analysis of public key cryptographic algorithms matters to the researches and development of blockchain. In cryptographic academia, it is generally recommended to design and analyze cryptographic schemes strictly by practising provable security theory, complexity theory, and proof techniques to validate proposed schemes.