Blockchain Developer FREE Blockchain Developer Consensus Algorithms and Protocols Questions and Answers 2

Question 1

What mechanism does Delegated Proof of Stake (DPoS) use to achieve consensus?

Accepted Answer

Token holders vote for a fixed number of delegates who validate blocks

Answer

DPoS allows token holders to elect a limited set of delegates responsible for producing blocks and validating transactions.

Question 2

Which consensus algorithm is specifically designed to tolerate up to one-third of nodes acting maliciously?

Accepted Answer

Practical Byzantine Fault Tolerance (PBFT)

Answer

PBFT can tolerate up to f Byzantine faulty nodes in a network of 3f+1 total nodes, meaning it handles just under one-third malicious participants.

Question 3

In Proof of Stake systems, what is the primary risk that slashing conditions are designed to prevent?

Accepted Answer

Validators signing conflicting blocks or performing equivocation

Answer

Slashing penalizes validators who sign two different blocks at the same height or otherwise act dishonestly, deterring equivocation.

Question 4

What is the key advantage of the Nakamoto consensus used in Bitcoin compared to classical BFT protocols?

Accepted Answer

It supports an open and permissionless set of participants

Answer

Nakamoto consensus allows any node to join or leave the network freely, making it suitable for open permissionless blockchains.

Question 5

In the Raft consensus algorithm, what happens when a follower node does not receive a heartbeat from the leader within the election timeout?

Accepted Answer

It becomes a candidate and initiates a new leader election

Answer

When a follower's election timeout elapses without receiving a heartbeat, it transitions to candidate state and starts a new election term.

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