CBCP Consensus Mechanisms 4

Question 1

What is 'Proof of Burn' and what problem was it designed to address?

Accepted Answer

Permanently sending coins to an unspendable address to gain mining rights; addresses energy waste of PoW

Answer

Proof of Burn requires validators to 'burn' (destroy) tokens by sending them to a verifiably unspendable address, demonstrating commitment without the energy cost of PoW mining.

Question 2

Which property of PBFT makes it unsuitable for large public blockchain networks?

Accepted Answer

Its O(n²) message complexity makes it unscalable to thousands of nodes

Answer

PBFT requires each node to communicate with every other node during each consensus round, resulting in O(n²) messages that become prohibitive as node count grows.

Question 3

In Avalanche consensus, what is a 'snowball' query and how does it build confidence?

Accepted Answer

Repeatedly sampling random validator subsets; accumulating sequential same-color responses increases confidence

Answer

Avalanche's Snowball protocol repeatedly samples small random subsets of validators; when consecutive rounds yield the same preference, confidence in that choice grows until a threshold is reached.

Question 4

What is the primary advantage of using a Verifiable Random Function (VRF) in consensus leader selection?

Accepted Answer

It allows a node to privately prove it won the lottery without revealing the result until needed

Answer

VRF allows a node to self-select as leader and generate a cryptographic proof verifiable by others, while keeping the selection secret until the block is announced — preventing targeted attacks.

Question 5

In Proof of Authority (PoA) consensus, what is the trade-off compared to Proof of Work?

Accepted Answer

PoA is faster and more efficient but sacrifices decentralization by relying on a set of approved validators

Answer

PoA achieves high throughput and energy efficiency by having known, approved validators, but this means trusting those authorities, which reduces decentralization and censorship resistance.

CBCP - Certified Blockchain Professional Practice Test

CBCP - Certified Blockchain Professional Practice Test

CBCP Consensus Mechanisms 4