Redactable Blockchain based on Unforgeable Signatures for Supporting Fast Verification

Redactable blockchain is an emerging topic in recent blockchain research. Its purpose is to delete or correct errors and harmful content on the chain without using hard forks. In other words, while preserving the public immutability of the blockchain, to allow some administrators or trusted centers with higher authority to modify the content on the blockchain without violating the integrity of the entire blockchain. In this paper, we proposed a redactable blockchain scheme based on unforgeable signatures. Compared with the existing blockchain editing solutions, this paper's solution can be efficiently and conveniently integrated into the current blockchain technology. This scheme's security is based on the collision-resistant hash function used by the original immutable blockchain and the unforgeability of the signature scheme. Besides, our solution can quickly confirm whether a chain has correctly implemented modifications issued by the central authority through the merge verification of signatures.