Blockchain_unit1

Which theorem states that a distributed system cannot simultaneously achieve Consistency, Availability, and Partition Tolerance?

• P vs NP Theorem

• CAP Theorem

• Brewer’s Theorem

• Byzantine Generals Theorem

In the context of distributed systems, what is a Byzantine node?

• A node that always follows the correct protocol

• A node that crashes and does not respond

• A node that behaves arbitrarily or maliciously

• A node that only stores data but does not process it

What problem does the Byzantine Generals Problem illustrate in distributed systems?

• How to ensure data redundancy

• How to achieve consensus in the presence of malicious actors

• How to scale distributed databases efficiently

• How to reduce energy consumption in consensus mechanisms

Which of the following best describes a blockchain?

• A centralized ledger stored in one location

• A distributed and immutable digital ledger

• A system that only allows encrypted transactions

• A peer-to-peer network that does not require consensus

What is a Merkle tree used for in blockchain technology?

• Encrypting transactions

• Storing smart contracts

• Efficiently verifying large datasets

• Preventing Sybil attacks

Which consensus algorithm is commonly used by Bitcoin?

• Proof of Work (PoW)

• Delegated Proof of Stake (DPoS)

• Proof of Stake (PoS)

• Practical Byzantine Fault Tolerance (PBFT)

Which of the following is NOT an advantage of blockchain technology?

• Decentralization

• Immutability

• Infinite scalability

• Enhanced security

What does "immutability" mean in the context of blockchain?

• Transactions can be modified by the network

• Data cannot be changed once it has been recorded

• The blockchain has an unlimited storage capacity

• Data cannot be changed once it has been recorded

What is the main advantage of using blockchain for decentralization?

• It ensures all operations are controlled by a single authority

• It allows for intermediary-free transactions and secure consensus

• It enables parallel computing across all nodes in a network

• It removes the need for cryptographic security

What is the primary role of cryptographic hashing in blockchain?

• Encrypting transactions
  

• Ensuring data integrity and immutability

• Controlling network access

• Speeding up transaction processing