Podcast
Questions and Answers
Which statement best describes the fundamental difference between crash faults and Byzantine faults?
Which statement best describes the fundamental difference between crash faults and Byzantine faults?
- Byzantine faults can be tolerated with fewer redundant nodes than crash faults.
- Crash faults always lead to a complete network partition, while Byzantine faults do not.
- Crash faults require a larger number of nodes for consensus compared to Byzantine faults.
- Crash faults are characterized by passive node failures, while Byzantine faults involve nodes acting maliciously. (correct)
A system with four nodes employing a BFT consensus mechanism experiences a permanent hardware failure in one node and a compromise by an attacker on another. Can the system continue to function correctly?
A system with four nodes employing a BFT consensus mechanism experiences a permanent hardware failure in one node and a compromise by an attacker on another. Can the system continue to function correctly?
- Yes, provided the compromised node is quickly isolated.
- Yes, consensus can be maintained with the remaining nodes.
- Yes, but the system will operate with reduced efficiency.
- No, the system cannot maintain consensus under these conditions. (correct)
In Paxos, consider a scenario where a proposer receives a promise that includes a previously accepted value. What action should the proposer take according to the Paxos protocol?
In Paxos, consider a scenario where a proposer receives a promise that includes a previously accepted value. What action should the proposer take according to the Paxos protocol?
- The proposer should use the previously accepted value with the highest ID in its proposal. (correct)
- The proposer should ignore the promise and continue with its original proposed value.
- The proposer should propose a completely new value to avoid conflicts.
- The proposer should abort the current consensus attempt.
Which of the following statements accurately describe characteristics of a permissioned blockchain model?
Which of the following statements accurately describe characteristics of a permissioned blockchain model?
In the Paxos algorithm, what guarantee does a majority of promises provide to a proposer?
In the Paxos algorithm, what guarantee does a majority of promises provide to a proposer?
In a Byzantine Fault Tolerance (BFT) system, if there are 3 faulty nodes, what is the minimum total number of nodes required to achieve consensus?
In a Byzantine Fault Tolerance (BFT) system, if there are 3 faulty nodes, what is the minimum total number of nodes required to achieve consensus?
Consider a scenario in the Byzantine Generals Problem with one good commander, one good lieutenant, and one faulty lieutenant. Under what condition(s) can consensus be achieved?
Consider a scenario in the Byzantine Generals Problem with one good commander, one good lieutenant, and one faulty lieutenant. Under what condition(s) can consensus be achieved?
What is the main purpose of Multi-Paxos?
What is the main purpose of Multi-Paxos?
Which of the following statements is/are false regarding classic Paxos?
Which of the following statements is/are false regarding classic Paxos?
In the Paxos algorithm, what accurately describes the roles a node can assume?
In the Paxos algorithm, what accurately describes the roles a node can assume?
Flashcards
Crash vs. Byzantine Faults
Crash vs. Byzantine Faults
Crash faults occur when nodes fail passively, while Byzantine faults involve nodes behaving maliciously.
Byzantine Fault Tolerance
Byzantine Fault Tolerance
To tolerate F Byzantine faults, you need at least 3F + 1 systems.
Paxos Proposer Action
Paxos Proposer Action
If a proposer in Paxos receives a promise with an already accepted value, it should use that value with the highest ID.
Permissioned Blockchain
Permissioned Blockchain
Signup and view all the flashcards
Paxos Promises' Role
Paxos Promises' Role
Signup and view all the flashcards
BFT Node Count
BFT Node Count
Signup and view all the flashcards
Byzantine Generals Problem
Byzantine Generals Problem
Signup and view all the flashcards
Multi-Paxos Purpose
Multi-Paxos Purpose
Signup and view all the flashcards
Classic Paxos Focus
Classic Paxos Focus
Signup and view all the flashcards
Node Roles in Paxos
Node Roles in Paxos
Signup and view all the flashcards
Study Notes
- Byzantine faults involve deliberate malicious behavior.
Question 2
- A system requires at least 4 systems to tolerate 1 Byzantine fault, according to the formula 3F+1, where F is the number of Byzantine faults.
- If one system permanently fails and another is compromised, the remaining systems cannot maintain consensus.
Question 3
- In Paxos, a proposer receiving a promise with an already accepted value will use the previously accepted value with the highest ID.
Question 4
- In a permissioned blockchain model, users are authenticated through a Membership Service Provider (MSP).
- Security and consensus are required in a permissioned blockchain.
- Transactions in a permissioned blockchain are only visible to authorized participants.
Question 5
- In the Paxos algorithm, a majority of promises ensures safety against conflicting proposals.
Question 6
- With 3 faulty nodes, 10 nodes are needed to reach consensus in a Byzantine Fault Tolerance (BFT) system, calculated by 3f + 1 = 3(3) + 1 = 10.
Question 7
- In a Byzantine Generals Problem with one good commander, one good lieutenant, and one faulty lieutenant, the consensus is impossible because the faulty lieutenant can mislead.
- Consensus is possible if there are additional good lieutenants.
Question 8
- Multi-Paxos aims to reach a consensus for a series of values.
- Multi-Paxos does not offer a termination guarantee.
Question 9
- Classic Paxos is designed to handle only crash faults.
- Classic Paxos achieves consensus on the value, not on ID.
Question 10
- In Paxos, a node can play one or more roles simultaneously.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
