Properties of Permissioned Blockchains

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What is a key benefit of state machine replication-based consensus in a permissioned blockchain?

Improved security against malicious nodes
Higher energy consumption
Enhanced scalability
No need to spend power, time, or bitcoin (correct)

What is the minimum number of nodes required to achieve consensus in a Byzantine Generals Problem with one commander, one good lieutenant, and one faulty lieutenant?

5
3
6
4 (correct)

Which of the following statements is true about Byzantine Dissemination Quorum?

Quorums can be dynamically adjusted based on network conditions
There is always a quorum available with no faulty replicas
Any two quorums have at least one correct replica in common (correct)
Quorums are only required for asynchronous networks

What is the primary purpose of consensus in a distributed system?

To ensure all nodes agree on a single state (D) Signup and view all the answers

Which of the following is NOT a synchronous consensus technique?

Byzantine General Model (B) Signup and view all the answers

What happens to a system using the BFT model when one system is permanently failed due to a hardware fault and another system is compromised by an attacker?

The system does not work at all (C) Signup and view all the answers

In the Paxos protocol, what is the purpose of the PROPOSE-ACCEPT phase?

To propose a new value and ensure its acceptance by all learners (A) Signup and view all the answers

What is a characteristic of the Paxos protocol?

Once a consensus is reached, Paxos cannot progress to another consensus (A) Signup and view all the answers

What is a characteristic of a closed network in the context of distributed consensus?

Nodes know each other (D) Signup and view all the answers

What is the reason for using state machine replication-based consensus in permissioned blockchains?

To provide a trusted and transparent system (A) Signup and view all the answers

Which of the following is a benefit of using state machine replication-based consensus over traditional consensus protocols?

Reduced energy consumption (A) Signup and view all the answers

What is the primary advantage of using RAFT protocol in distributed consensus?

Strong fault tolerance (D) Signup and view all the answers

What is the key property of quorums in Byzantine dissemination?

Any two quorums have at least one correct replica in common (B) Signup and view all the answers

What is the minimum number of replicas required to reach consensus in the presence of Byzantine faults?

3f + 1 (A) Signup and view all the answers

What is the correct sequence of operations in the PBFT algorithm?

iv, i, ii, iii (C) Signup and view all the answers

What is the minimum quorum size required for PBFT to be safe in an asynchronous environment?

2f + 1 (A) Signup and view all the answers

What is the primary use of Hyperledger frameworks?

Building permissioned blockchains for organizations (B) Signup and view all the answers

How do Byzantine faults differ from crash faults?

Byzantine faults are more severe than crash faults (B) Signup and view all the answers