Core Blockchain Data Structures Flashcards
7 cards from real Blockchain Technology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Core Blockchain Data Structures flashcards as text
What is a 'block height'?
Answer: The number of blocks preceding a given block in the chain
Block height is the count of blocks between a given block and the genesis block.
Why might a blockchain use a Merkle tree instead of simply hashing the concatenation of all transactions?
Answer: To enable efficient inclusion proofs and partial verification
A tree structure supports compact membership proofs, which a single concatenated hash cannot provide.
In Ethereum, what three tries are committed to in each block header?
Answer: State, transactions, and receipts tries
Ethereum headers commit to the state root, transactions root, and receipts root.
What is the purpose of a Bloom filter in some block headers?
Answer: To allow quick probabilistic checks for logs/events in a block
Bloom filters let clients quickly test whether a block likely contains relevant logs without scanning everything.
What does collision resistance in a hash function prevent?
Answer: Two different inputs producing the same hash output
Collision resistance makes it computationally infeasible to find two distinct inputs with identical hashes.
How does a full node verify the Merkle root of a received block?
Answer: It recomputes the tree from the block's transactions and compares roots
A full node rebuilds the Merkle tree from all transactions and confirms the computed root matches the header.
What is the main consequence of finding a hash collision in a blockchain's hash function?
Answer: It could allow forging data while keeping the same hash, breaking integrity
A practical collision would let an attacker substitute data without changing the hash, undermining chain integrity.