CBSA Core Blockchain Principles 3

Question 1

What problem does the Byzantine Generals Problem illustrate in the context of distributed blockchain networks?

Accepted Answer

How to reach consensus among nodes when some may act maliciously or fail

Answer

The Byzantine Generals Problem models the challenge of achieving reliable agreement in a distributed system where some participants may send conflicting or false information.

Question 2

What is a '51% attack' in a Proof of Work blockchain?

Accepted Answer

When an entity controls more than half the network's hash rate, enabling double-spend attacks

Answer

Controlling majority hash power lets an attacker secretly mine an alternate chain, enabling them to reverse transactions and double-spend.

Question 3

In Ethereum's account model, what is the difference between an Externally Owned Account (EOA) and a Contract Account?

Accepted Answer

EOAs are controlled by private keys; Contract Accounts are controlled by smart contract code

Answer

EOAs are managed by users with private keys and can initiate transactions, while Contract Accounts execute predefined code when triggered by transactions.

Question 4

What does 'gas' represent in the Ethereum blockchain?

Accepted Answer

A unit measuring computational effort required to execute operations

Answer

Gas quantifies the computational work required for each operation, and users pay gas fees to incentivize validators to include their transactions.

Question 5

Which consensus mechanism selects block validators based on the amount of cryptocurrency they lock up as collateral?

Accepted Answer

Proof of Stake

Answer

Proof of Stake selects validators proportional to their staked collateral, replacing energy-intensive hash computation with economic stake.

(CBSA) Certified Blockchain Solution Architect Practice Test

(CBSA) Certified Blockchain Solution Architect Practice Test

CBSA Core Blockchain Principles 3