CBCP Blockchain Fundamental 5 — Questions and Answers
Question 1: What is a 'distributed ledger' and how does it differ from a traditional centralized database?
- A ledger stored on a single highly redundant server cluster rather than multiple independent nodes
- A record-keeping system replicated across multiple independent nodes with no single controlling authority (Correct answer)
- A database partitioned across geographic data centers owned by one organization
- A ledger that only stores hashes of data rather than the data itself
Correct answer: A record-keeping system replicated across multiple independent nodes with no single controlling authority
A distributed ledger is shared and synchronized across many nodes independently operated, eliminating the single point of control and failure inherent in centralized databases.
Question 2: In the Bitcoin network, what determines the mining difficulty adjustment?
- The total number of transactions in the mempool
- The network targets an average block time of 10 minutes, adjusting difficulty every 2,016 blocks (Correct answer)
- The current Bitcoin price relative to miner electricity costs
- The number of active nodes on the network at any given time
Correct answer: The network targets an average block time of 10 minutes, adjusting difficulty every 2,016 blocks
Bitcoin's protocol recalculates mining difficulty every 2,016 blocks (approximately two weeks) to maintain the 10-minute average block interval regardless of total hash rate.
Question 3: What is the purpose of the UTXO (Unspent Transaction Output) model used in Bitcoin?
- To cache recently used wallet addresses for faster lookup
- To track discrete units of cryptocurrency that have been received but not yet spent, preventing double-spending (Correct answer)
- To record validator votes during the consensus process
- To store metadata about smart contract state changes
Correct answer: To track discrete units of cryptocurrency that have been received but not yet spent, preventing double-spending
The UTXO model treats each coin as a discrete output; spending requires referencing existing UTXOs, and any remainder creates a new UTXO, ensuring each coin is spent only once.
Question 4: How does the account-based model used by Ethereum differ from Bitcoin's UTXO model?
- Ethereum records balances as account states rather than tracking individual unspent outputs (Correct answer)
- Ethereum requires all users to maintain a minimum UTXO to keep accounts active
- Ethereum uses UTXOs but groups them by wallet address
- Ethereum converts all UTXOs to a single balance only at the time of a transaction
Correct answer: Ethereum records balances as account states rather than tracking individual unspent outputs
Ethereum maintains a global state of account balances that are updated with each transaction, simplifying smart contract logic compared to the UTXO model.
Question 5: What is 'gas' in the context of the Ethereum blockchain?
- A native token separate from ETH used to pay block producers
- A unit measuring the computational effort required to execute operations, paid in ETH by the sender (Correct answer)
- The fuel burned by miners during Proof of Work hashing
- A penalty fee charged when a smart contract fails validation
Correct answer: A unit measuring the computational effort required to execute operations, paid in ETH by the sender
Gas quantifies the computation each Ethereum operation requires; users pay gas fees in ETH to compensate validators and prevent network spam.
Question 6: Which type of node in a blockchain network stores a complete copy of the entire transaction history?
- Light node (SPV node)
- Full node (Correct answer)
- Mining node only
- Archival super-node
Correct answer: Full node
A full node independently downloads and validates every block and transaction from the genesis block, maintaining the complete chain history.
Question 7: What is 'tokenization' in the blockchain ecosystem?
- The process of generating new cryptographic keys for wallet security
- The conversion of real-world assets or rights into digital tokens on a blockchain (Correct answer)
- A technique for compressing transaction data into shorter token strings
- The act of destroying coins to reduce overall token supply
Correct answer: The conversion of real-world assets or rights into digital tokens on a blockchain
Tokenization represents ownership, rights, or value of real-world assets (real estate, art, equity) as digital tokens on a blockchain, enabling fractional ownership and programmable transfer.
CBCP Blockchain Fundamental 5
What is a 'distributed ledger' and how does it differ from a traditional centralized database?