Dual-Accountability Redactable Blockchain Supporting Controllable Modification Times

Blockchain, a tamper-proof ledger, enables consensus in untrusted settings. While its permanence ensures data integrity, regulatory changes necessitate adaptable blockchains. Redactable blockchains permit authorized alterations to prevent misinformation, addressing legal and ethical challenges. Existing solutions often lack limits on modifications and decentralized accountability. This paper introduces DRBCMT, a novel approach using a committee mechanism, K-times hash values, Multi-Signature, and chameleon hash. We outline a redactable blockchain framework, provide construction examples, and validate its security and efficiency through experiments. Our results show that DRBCMT is practical with minimal overhead versus traditional redactable blockchains.