CBCP Ethereum 5 — Questions and Answers
Question 1: What is 'MEV' (Maximal Extractable Value) in the context of Ethereum?
- Profit validators or block proposers can earn by reordering, inserting, or censoring transactions within a block (Correct answer)
- The maximum gas fee a user can set for a transaction
- The total ETH issuance per epoch for validators
- The maximum value locked in a single DeFi protocol
Correct answer: Profit validators or block proposers can earn by reordering, inserting, or censoring transactions within a block
MEV arises because block proposers control transaction ordering, enabling strategies like sandwich attacks, arbitrage, and liquidations.
Question 2: Which Ethereum token standard introduces a 'hook' mechanism allowing contracts to react when they receive tokens?
- ERC-777 (Correct answer)
- ERC-20
- ERC-1155
- ERC-4626
Correct answer: ERC-777
ERC-777 adds tokensReceived and tokensToSend hooks called on sender/receiver contracts, enabling richer composability.
Question 3: What is the 'Beacon Chain' withdrawal credential type '0x01' used for?
- Linking a validator's withdrawal address to a specific Ethereum execution layer (0x01) address for ETH withdrawals (Correct answer)
- Identifying a validator using a BLS public key hash for deposits
- Marking a validator as fully exited from the consensus layer
- Encoding the initial deposit amount in hexadecimal
Correct answer: Linking a validator's withdrawal address to a specific Ethereum execution layer (0x01) address for ETH withdrawals
0x01 withdrawal credentials specify an Ethereum execution address, enabling Shanghai-era partial and full withdrawals.
Question 4: In Ethereum's account abstraction roadmap, what does EIP-4337 enable without requiring consensus-layer changes?
- Smart contract wallets that can initiate transactions using a separate mempool and bundler infrastructure (Correct answer)
- Native multi-call support for EOAs at the protocol level
- Gasless transactions sponsored directly by miners
- Elimination of the nonce requirement for smart contracts
Correct answer: Smart contract wallets that can initiate transactions using a separate mempool and bundler infrastructure
EIP-4337 achieves account abstraction via UserOperations, a dedicated alt-mempool, and bundler nodes — no hard fork needed.
Question 5: What does the Ethereum state transition function's 'intrinsic gas' component cover?
- A base cost charged before execution for transaction size, zero/non-zero bytes, and access list entries (Correct answer)
- The gas cost of the first SSTORE in a transaction
- The refund issued for clearing storage slots
- The gas consumed by precompiled contracts
Correct answer: A base cost charged before execution for transaction size, zero/non-zero bytes, and access list entries
Intrinsic gas (minimum 21,000 for a simple transfer) is deducted upfront and accounts for calldata bytes and access list overhead.
Question 6: Which Ethereum consensus mechanism property ensures that once a block is finalized, it cannot be reverted without destroying at least 1/3 of all staked ETH?
- Accountable safety via Casper FFG slashing conditions (Correct answer)
- LMD-GHOST fork-choice rule weight
- Validator set rotation entropy
- BLS signature aggregation threshold
Correct answer: Accountable safety via Casper FFG slashing conditions
Casper FFG's slashing conditions make equivocating (voting for two conflicting finalized checkpoints) economically catastrophic.
Question 7: What is the primary purpose of Ethereum's 'Verkle Tree' upgrade planned post-Cancun?
- Replace Merkle Patricia Tries with smaller witnesses to enable stateless clients and reduce node storage requirements (Correct answer)
- Increase transaction throughput by 10x through parallel execution
- Enable cross-shard communication without bridges
- Replace ECDSA signatures with post-quantum cryptography
Correct answer: Replace Merkle Patricia Tries with smaller witnesses to enable stateless clients and reduce node storage requirements
Verkle Trees produce compact proofs (witnesses) so nodes can verify blocks without storing the full state, enabling stateless Ethereum.
CBCP Ethereum 5
What is 'MEV' (Maximal Extractable Value) in the context of Ethereum?