Online Courses
Blockchain Security
Online Courses
Blockchain Security
  • Blockchain Security
  • Fundamentals of Blockchain Security
    • Introduction to blockchain
    • The promises of blockchain
    • Inside the blockchain hype
    • Blockchain structures
    • What is public-key cryptography?
      • How does public-key cryptography work?
      • Public-key cryptography in the blockchain
    • Security assumptions of public-key cryptography
      • Quantum computing
    • Hash function in blockchain
      • Properties of hash functions
      • Hash functions in the blockchain
      • Blockchain security hash key functions
    • Quiz
  • Consensus Algorithm Security
    • Introduction
      • The Byzantine generals problem
      • Security via scarcity
      • Common blockchain consensus algorithms
      • The longest chain rule
    • Proof of work
      • Inside PoW mining
    • Attacking proof of work
      • The 51% attack
      • Denial of service: Artificial difficulty increases
    • Proof of stake
      • Choosing the block creator
    • Attacking PoS consensus
      • XX% attack and the PoS "timebomb"
      • Fake stake attacks
      • Long-range attack
      • Nothing at stake problem
      • Sour milk attack
    • Quiz
  • Blockchain in Action
    • Nodes and network
      • Inside the node
      • How blocks are created
    • Attacking block creation
      • Denial-of-service
      • Frontrunning
      • Selfish mining
      • SPV mining
    • Attacking blockchain nodes
      • Blockchain software misconfiguration
      • Denial of service
      • Malicious transactions
    • Attacking the blockchain network
      • Eclipse attack
      • Routing attack
      • Sybil attack
    • Quiz
  • Smart Contract Security
    • What are smart contracts?
      • Smart contracts
    • General programming vulnerabilities
      • Arithmetic vulnerabilities
      • Right-to-left control character
    • Blockchain vulnerabilities
    • Ethereum vulnerabilities
    • Quiz
  • Beyond the Basics
    • Alternative distributed ledger architectures
      • Introduction to DAGs
      • Introduction to block lattices
      • Introduction to sidechains
    • Second-level blockchain protocols
      • How a state channel works
    • Advanced cryptography in blockchain
      • Multisignatures
      • Zero-knowledge proofs
      • Stealth addresses
      • Ring signatures
      • Commitment schemes
    • Quiz
  • Cumulative Quiz
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  • Question 1
  • Question 2
  • Question 3
  • Question 4
  1. Consensus Algorithm Security

Quiz

Question 1

Which of the following are included in the header of a Proof of Stake block?

Solution

  • Previous block hash

  • Timestamp

  • Transaction root

Question 2

Which of the following attacks requires the attacker to have stake on a Proof of Stake blockchain?

Solution

  • XX% attack

  • Long-range attack

Question 3

Which of the following are reasons that a divergent blockchain can be created in a Proof of Work blockchain?

Solution

  • Statistical probability

  • A 51% attack

Question 4

Which of the following algorithms uses parts of a computer as its scarce resource?

Solution

  • Proof of Space

  • Proof of Work

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Last updated 9 months ago