Merging with Mainnet
Merging with Mainnet
Since genesis, proof-of-work has secured Mainnet. This is the Ethereum blockchain we're all used to—it contains every transaction, smart contract, and balance since it began in July 2015.
Throughout Ethereum's history, developers have been hard at work preparing for an eventual transition away from proof-of-work to proof-of-stake. On December 1, 2020, the Beacon Chain was created, which has since existed as a separate blockchain to Mainnet, running in parallel.
The Beacon Chain has not been processing Mainnet transactions. Instead, it has been reaching consensus on its own state by agreeing on active validators and their account balances. After extensive testing, the Beacon Chain's time to reach consensus on more is rapidly approaching. After The Merge, the Beacon Chain will be the consensus engine for all network data, including execution layer transactions and account balances.
The Merge represents the official switch to using the Beacon Chain as the engine of block production. Mining will no longer be the means of producing valid blocks. Instead, the proof-of-stake validators assume this role and will be responsible for processing the validity of all transactions and proposing blocks.