The Beacon Chain, also referred to as the coordination layer, is a fundamental component of Ethereum 2.0. It brings Proof of Stake to Ethereum 1 and operates in conjunction with it. Its key responsibilities include:
Here's a breakdown of some important terms and concepts related to the Beacon Chain:
Slots: Each slot represents a 12-second time period during which a randomly selected validator can propose a block. Not every slot necessarily contains a block. Validators are divided into committees, with one chosen as the aggregator while the others attest. After each epoch (comprising 32 slots), validators are reshuffled into new committees, with a minimum of 128 validators per committee.
Epoch: An epoch comprises 32 slots and lasts approximately 6.4 minutes. Epochs play a crucial role in managing the validator queue and determining finality.
Deposit Contract: The Deposit contract serves as the gateway from Ethereum 1.0 to Ethereum 2.0. It's a smart contract on Ethereum 1.0 that accepts transactions with a minimum of 1 ETH and valid input data, which is used by Ethereum 2.0 beacon nodes to credit each validator.
Input Data: Input data, also known as deposit data, is an 842-character sequence generated by users. It contains the validator's public key and withdrawal public key, signed by the validator's private key. This data must be included in the transaction to the deposit contract for identification by the beacon chain.
Validator: Validators must deposit 32 ETH into the validator deposit contract on Ethereum 1.0. Validator operators are responsible for running validator nodes, which propose blocks and sign attestations. Validators must be online at least 50% of the time to earn positive returns.
Eligible for Activation & Estimated Activation: These terms refer to validators in a pending state whose deposits have been recognized by the ETH2 chain. An estimated activation timestamp is calculated for validators in a queue.
Unique Index: Each validator is assigned a unique index.
Current Balance & Effective Balance: The current balance is the amount of ETH held by a validator, while the effective balance is a value derived from it and determines rewards or penalties. The effective balance can never exceed 32 ETH and can be increased by adding 1.25 ETH to the effective balance.
Slasher: The slasher is a separate entity that works in conjunction with a beacon node to detect malicious activity by validators, such as attestations that violate the rules.
Slashable Offenses: These include attestation violations, double voting, surround votes, and proposer violations, which can result in penalties or slashing.
Block Proposer: A validator chosen by the beacon chain to propose the next block.
Block Status: Blocks can be proposed, scheduled, missed/skipped, or orphaned based on the actions of validators.