Chapter 6 - Assessment

Question 1

What does SPV stand for?
Simplified Payment Verification

Question 2

How can a transaction with zero confirmations be considered effectively settled?

• If a transaction has been validated by a node and they will include it in a block, then it can be considered effectively settled.

• If a transaction has been validated by a number of nodes who share transactions received with one another in real time, then it can be safely assumed that the transaction is settled.

• By increasing the fees associated with your transaction you can increase the likelihood of your transaction being validated by a miner.

• O confirmation transactions cannot be considered settled.

Question 3

Given the following list of actions. What is the correct sequence of events for an SPV transaction?

Action	Sequence (1-6)
Broadcast the transaction to the network.	4
Query random subset of miners for transaction status.	5
Store the chain of block headers locally.	1
Transaction can be safely considered settled and goods can be released to customer.	6
Verify the UTXO can create the same Merkle root as in your local storage of headers.	3
Receive the Merkle path for the UTXOs of the transaction from either payer or request from nodes.	2

Question 4

What techniques can help increase the security for network users in the event of an attacker trying to extend a dishonest chain tip that includes double spends?

• mAPI

• MinerID

• Coinbase Maturity Rule

• All of the above.

Question 5

Can offline transactions be securely performed in Bitcoin?

• Yes, for the sender only.

• Yes, for the receiver only.

• Yes, for either the sender or receiver.

• No