Great Consensus Cleanup Revival
Posted by AntoineP
Mar 19, 2025/17:36 UTC
In a recent discussion, an innovative suggestion was made regarding the implementation of Bitcoin Improvement Proposals (BIPs). The idea revolves around enhancing the security and integrity of coinbase transactions within the Bitcoin network. By setting the nLockTime of coinbase transactions to one less than the block height and requiring that their nSequence is not final, a more robust enforcement mechanism for timelocks can be established. This adjustment ensures that timelocks are consistently verified across all transactions, including coinbase ones.
The significance of this proposal extends beyond its immediate impact on transaction verification. It addresses a potential vulnerability exposed by the removal of checkpoints from Bitcoin Core's validation process. Without these checkpoints, there exists a theoretical possibility for a chain to include a coinbase transaction from before the activation of BIP34 that could still commit to a block height post the Consensus Cleanup (CC) activation without violating current consensus rules. This scenario would necessitate a reactivation of BIP30 validation to prevent the acceptance of duplicate coinbase transactions. However, by mandating that the nSequence of coinbase transactions remain non-final, the system inherently prevents the occurrence of two transactions with identical transaction identifiers (txids), thereby obviating the need for BIP30 validation after the CC activation height.
This approach not only simplifies the validation logic post-CC activation but also fortifies the network against potential threats arising from the historical relaxation of certain validation checks. While the practical implications might be minimal under normal operation, the adoption of this measure could significantly enhance the overall resilience and security of the Bitcoin blockchain.
TLDR
Join Our Newsletter
We’ll email you summaries of the latest discussions from authoritative bitcoin sources, like bitcoin-dev, lightning-dev, and Delving Bitcoin.
Explore all Products
We'd love to hear your feedback on this project?
Give Feedback