Challenges in Blockchain Consensus Mechanisms BFC Practice Questions (Page 4)

Questions 16–20

1. 16foundation · easy

   In a Proof of Work blockchain, what is the primary reason for the high latency (time to finality) compared to permissioned consensus mechanisms?

   • AThe requirement that every transaction must be validated by a central authority before being added to the blockchain.
   • BThe requirement for all nodes to store the entire transaction history, which slows down the validation process.
   • CThe need to encrypt all transactions using complex cryptographic algorithms that take significant time to process.
   • DThe need for multiple confirmations to ensure that a block is not orphaned due to network propagation delays.
   Reveal Solution Discussion Select an answer first
2. 17foundation · easy

   Why is governance a significant challenge in public blockchain consensus mechanisms?

   • ABecause the consensus mechanism requires unanimous agreement from all nodes, which is impossible to achieve.
   • BBecause the consensus mechanism itself is controlled by a single entity that makes all upgrade decisions.
   • CBecause there is no central authority to make decisions, and reaching consensus among diverse stakeholders (miners, developers, users) is difficult.
   • DBecause all upgrades must be approved by a government regulator before implementation.
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4. 18expert · hard

   A blockchain consortium is facing a governance crisis. A proposal to change the consensus mechanism from PBFT to a new BFT variant has been approved by a majority of validators, but a powerful minority threatens to fork the network. The consortium wants to maintain network integrity and avoid a split. What is the most effective approach?

   • AForce the upgrade through a supermajority vote
   • BNegotiate with the minority to address their concerns
   • CProceed with the upgrade and accept the fork
   • DDelay the upgrade indefinitely
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5. 19application · medium

   A fintech startup is building a cross-border payment system that must settle transactions in under 2 seconds and handle peak loads of 5,000 transactions per second. They are evaluating consensus mechanisms and have ruled out Proof of Work due to latency. Which consensus approach would best meet their throughput and latency requirements while still providing finality?

   • AProof of Elapsed Time with random leader selection
   • BProof of Stake with a large, open validator set
   • CProof of Authority with a single validator node
   • DDelegated Proof of Stake with a small set of elected block producers
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6. 20application · medium

   A global payments company is deploying a blockchain network that uses a permissioned consensus mechanism. They must comply with anti-money laundering (AML) regulations that require transaction finality and the ability to reverse erroneous transactions. Which consensus feature is most critical for regulatory compliance?

   • AHigh energy efficiency
   • BOpen participation
   • CProbabilistic finality
   • DDeterministic finality
   Reveal Solution Discussion Select an answer first