FREE CBE Consensus Mechanisms Questions and Answers

Question 1

What is the primary goal of consensus mechanisms in blockchain?

Accepted Answer

Achieve agreement among nodes

Answer

The primary goal of consensus mechanisms in blockchain is to achieve agreement among all participating nodes regarding the validity of transactions and the order of blocks. In a decentralized network, these mechanisms ensure that a single, consistent version of the ledger is maintained, preventing double-spending and maintaining trust without a central authority.

Question 2

Which consensus algorithm is used by Bitcoin?

Accepted Answer

Proof of Work

Answer

Bitcoin, the first and most well-known cryptocurrency, utilizes the Proof of Work (PoW) consensus algorithm. In PoW, miners compete to solve a complex computational puzzle to validate transactions and add new blocks to the blockchain. The first miner to find the solution earns the right to add the block and receive a reward.

Question 3

Which of the following is a drawback of Proof of Work?

Accepted Answer

High energy consumption

Answer

A significant drawback of Proof of Work (PoW) consensus mechanisms, as used by Bitcoin, is their high energy consumption. Miners expend vast amounts of computational power to solve cryptographic puzzles, leading to substantial electricity usage and environmental concerns. This energy expenditure is necessary to secure the network but comes at a considerable cost.

Question 4

What is a key feature of Proof of Stake?

Accepted Answer

Validator chosen by staked coins

Answer

In Proof of Stake (PoS) consensus mechanisms, validators are chosen to create new blocks based on the amount of cryptocurrency they have 'staked' or locked up as collateral. The more coins a participant stakes, the higher their chance of being selected to validate transactions and earn rewards. This mechanism aims to be more energy-efficient than Proof of Work.

Question 5

Which consensus method uses a reputation system for validator selection?

Accepted Answer

Proof of Authority

Answer

Proof of Authority (PoA) is a consensus mechanism where validators are pre-approved and known entities. Their identity and reputation are critical for their selection and ability to validate transactions. This system relies on trust in these authorized participants, making reputation a core component of validator selection.

CBE - Certified Blockchain Expert Practice Test

CBE - Certified Blockchain Expert Practice Test

FREE CBE Consensus Mechanisms Questions and Answers