CBSA Consensus Mechanisms 2

Question 1

Which consensus mechanism is used by Hyperledger Fabric to order transactions before they are committed to the ledger?

Accepted Answer

Raft or Kafka-based ordering service

Answer

Proof of Work

Answer

Delegated Proof of Stake

Answer

Byzantine Fault Tolerance voting

Question 2

In a Practical Byzantine Fault Tolerant (PBFT) network with 10 nodes, what is the maximum number of faulty nodes the system can tolerate?

Accepted Answer

3

Answer

1

Answer

2

Answer

4

Question 3

What is the primary purpose of the 'finality' property in blockchain consensus mechanisms?

Accepted Answer

To ensure a committed block cannot be reversed or reorganized

Answer

To maximize transaction throughput

Answer

To reduce block propagation latency

Answer

To encrypt transaction data permanently

Question 4

Ethereum's move from Proof of Work to Proof of Stake (The Merge) primarily aimed to achieve which benefit?

Accepted Answer

Reduce energy consumption by ~99.95%

Answer

Increase block size limit

Answer

Enable smart contract execution

Answer

Eliminate transaction fees

Question 5

In Delegated Proof of Stake (DPoS), token holders participate in consensus by:

Accepted Answer

Voting for a fixed set of elected delegates who produce blocks

Answer

Running full mining nodes themselves

Answer

Locking tokens in a smart contract to earn rewards directly

Answer

Solving cryptographic puzzles proportional to their stake

Question 6

Which characteristic best distinguishes Proof of Authority (PoA) from Proof of Stake (PoS)?

Accepted Answer

PoA relies on verified real-world identities rather than economic stake

Answer

PoA validators are selected based on their token holdings

Answer

PoA achieves consensus through computational puzzles

Answer

PoA requires more validators than PoS to reach finality

Question 7

The 'nothing-at-stake' problem is a known vulnerability in which type of consensus mechanism?

Accepted Answer

Naive Proof of Stake implementations

Answer

Proof of Work

Answer

Proof of Authority

Answer

Federated Byzantine Agreement