TY - JOUR
T1 - Escaping From Consensus
T2 - Instantly Redactable Blockchain Protocols in Permissionless Setting
AU - Li, Xinyu
AU - Xu, Jing
AU - Yin, Lingyuan
AU - Lu, Yuan
AU - Tang, Qiang
AU - Zhang, Zhenfeng
N1 - Funding Information:
The work of Xinyu Li was supported in part by the National Key R&D Program of China under Grant 2020YFB1005801, and in part by Innovation Technology Fund under Grant ITS/224/20FP. The work of Jing Xu was supported in part by the National Natural Science Foundation of China under Grant 62172396. The work of Yuan Lu was supported in part by the National Natural Science Foundation of China under Grant 62102404, and in part by Youth Innovation Promotion Association CAS. The work of Qiang Tang was supported in part by gifts from Ethereum Foundation, Stellar Foundation and Protocol Labs. The work of Zhenfeng Zhang was supported in part by the National Key R&D Program of China under Grant 2022YFB2701600.
Publisher Copyright:
© 2004-2012 IEEE.
PY - 2023/9/1
Y1 - 2023/9/1
N2 - Blockchain technologies have drawn a lot of attentions, and its immutability is paramount to applications requiring persistent records. However, tremendous real-world incidents have exposed the harm of strict immutability, such as the illicit data stored on Bitcoin and the loss of millions of dollars in vulnerable smart contracts. Moreover, 'Right to be Forgotten' has been imposed in new General Data Protection Regulation (GDPR) of European Union, which is incompatible with blockchain's immutability. Therefore, it is imperative to design efficient redactable blockchain in a controlled way. In this paper, we present a generic design of redactable blockchain protocols in the permissionless setting, applied to both proof-of-stake and proof-of-work blockchains. Our protocol can (1) maintain the same adversary bound requirement as the underlying blockchain, (2) support various network environments, (3) offer public verifiability for any redaction, and (4) achieve instant redaction, even only within one slot in the best case, which is desirable for redacting harmful data. Furthermore, we define the first ideal protocol of redactable blockchain and conduct security analysis following the language of universal composition. Finally, we develop a proof-of-concept implementation showing that the overhead remains minimal for both online and re-spawning nodes, which demonstrates the high efficiency of our design.
AB - Blockchain technologies have drawn a lot of attentions, and its immutability is paramount to applications requiring persistent records. However, tremendous real-world incidents have exposed the harm of strict immutability, such as the illicit data stored on Bitcoin and the loss of millions of dollars in vulnerable smart contracts. Moreover, 'Right to be Forgotten' has been imposed in new General Data Protection Regulation (GDPR) of European Union, which is incompatible with blockchain's immutability. Therefore, it is imperative to design efficient redactable blockchain in a controlled way. In this paper, we present a generic design of redactable blockchain protocols in the permissionless setting, applied to both proof-of-stake and proof-of-work blockchains. Our protocol can (1) maintain the same adversary bound requirement as the underlying blockchain, (2) support various network environments, (3) offer public verifiability for any redaction, and (4) achieve instant redaction, even only within one slot in the best case, which is desirable for redacting harmful data. Furthermore, we define the first ideal protocol of redactable blockchain and conduct security analysis following the language of universal composition. Finally, we develop a proof-of-concept implementation showing that the overhead remains minimal for both online and re-spawning nodes, which demonstrates the high efficiency of our design.
KW - Blockchain
KW - proof-of-stake
KW - proof-of-work
KW - redactable blockchain
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U2 - 10.1109/TDSC.2022.3212601
DO - 10.1109/TDSC.2022.3212601
M3 - Article
AN - SCOPUS:85139818611
SN - 1545-5971
VL - 20
SP - 3699
EP - 3715
JO - IEEE Transactions on Dependable and Secure Computing
JF - IEEE Transactions on Dependable and Secure Computing
IS - 5
ER -