info
The Merge was executed on September 15, 2022.
The Merge was an Ethereum upgrade that merged theBeacon Chain into Ethereum Mainnet, turning Mainnet into a combination of an execution layer andconsensus layer.The Merge transitioned Mainnet from proof of work to proof of stake consensus.
You can run Besu as an execution client with:
- Any consensus client on Mainnet.
- Any consensus client on a testnet.
- Teku on Mainnet.
- Teku on a testnet.
Execution and consensus clients
After The Merge, a full Ethereum Mainnet node is a combination of an execution client (previouslycalled an Ethereum 1.0 client) anda consensus client (previously called an Ethereum2.0 client).
Execution and consensus clients communicate with each other using the Engine API.
Execution clients
Execution clients, such as Besu, manage the execution layer, including executing transactions andupdating the world state.Execution clients serve JSON-RPC API requests and communicatewith each other in a peer-to-peer network.
Consensus clients
Consensus clients, such as Teku, contain beacon node and validator client implementations.The beacon node is the primary link to the Beacon Chain (consensus layer).The validator client performs validator duties on the consensus layer.Consensus clients serve REST API requests andcommunicate with each other in a peer-to-peer network.
What happened during The Merge
Before The Merge, the execution and consensus clients' configurations were updated to listen for acertain total terminal difficulty (TTD) to be reached.
info
The TTD is a specific value for the total difficulty, which is the sum of the proof-of-work miningdifficulty for all blocks up to some point in the blockchain.
The consensus layer enabled the Merge configuration (Bellatrix) before reaching the TTD.Once the execution layer blocks reached the TTD, the Beacon Chain merged into Ethereum Mainnet, andEthereum transitioned to a proof of stake network.
tip
After The Merge, a Mainnet node operator must run both an execution client and a beacon node at thesame time.To become a validator, you must also run a validator client (either in the same process as thebeacon nodeor separately.
After The Merge, validators earn rewardsfor performing validator duties, and feerecipientsalso earn rewards for the inclusion of execution layer transactions.
