A hard fork in blockchain occurs when the protocol is updated in a way that is not backward-compatible, meaning nodes running the old version will no longer accept blocks created by the new version, and vice versa. To verify a hard fork, nodes must follow these steps:
Protocol Update: Nodes must upgrade their software to the new version that implements the hard fork rules. This ensures they understand and enforce the new consensus rules.
Block Validation: After the upgrade, nodes will only accept blocks that comply with the new protocol rules. If a block violates the new rules, it will be rejected, even if it was valid under the old rules.
Consensus Check: Nodes communicate with each other to ensure they are all following the same new rules. If a majority of the network has upgraded and is enforcing the new rules, the hard fork is considered successful, and the blockchain splits into two separate chains (the old one and the new one).
Example:
In Bitcoin's history, the Bitcoin Cash (BCH) hard fork occurred in August 2017. Nodes that wanted to support BCH had to upgrade their software to the new version, which changed the block size limit from 1 MB to 8 MB. Nodes running the old Bitcoin software rejected blocks larger than 1 MB, while BCH nodes accepted them. This led to a permanent split in the blockchain.
Cloud Recommendation:
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