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ACHIEVING CONSENSUS

In this email exchange on the metzdowd Cryptography Mailing List, Satoshi Nakamoto addresses the issue of achieving consensus in the Bitcoin system. Consensus is a critical aspect of any decentralized system, ensuring that all participants agree on the state of the shared ledger.

Nakamoto explains that the proof-of-work chain is the solution to the synchronization problem and to knowing what the globally shared view is without having to trust anyone. He describes how transactions propagate throughout the network, with nodes accepting the first version of a transaction they see and refusing subsequent ones. Nodes then “vote” for their viewpoint of which transaction they saw first by including it in their proof-of-work effort.

He further explains that when a node finds a proof-of-work, the new block is propagated throughout the network and everyone adds it to the chain. Any nodes that had the other transaction will stop trying to include it in a block, since it’s now invalid according to the accepted chain.

This email provides a deep insight into the mechanisms that Nakamoto designed to achieve consensus in the Bitcoin system. It showcases the robustness of the Bitcoin protocol and Nakamoto’s deep understanding of the challenges inherent in a decentralized system.