Consensus Mechanisms Flashcards
7 cards from real Blockchain Technology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Consensus Mechanisms flashcards as text
What is the main energy advantage of Proof of Stake over Proof of Work?
Answer: It eliminates competitive hashing, drastically cutting energy use
PoS selects proposers by stake rather than energy-intensive hashing, reducing consumption by over 99%.
In sharded blockchains, why is cross-shard consensus challenging?
Answer: Transactions spanning shards require coordination and atomicity across separate consensus groups
Cross-shard transactions must remain atomic and consistent across independently-validated shards, complicating consensus.
What is the 'liveness' property of a consensus protocol?
Answer: The network keeps making progress and confirming new transactions
Liveness guarantees the system continues to process and commit transactions over time.
What is the 'safety' property of a consensus protocol?
Answer: No two honest nodes finalize conflicting blocks
Safety ensures honest participants never commit to contradictory states or forks.
Under the CAP theorem framing, BFT consensus systems like Tendermint typically favor which properties during a partition?
Answer: Consistency over availability
Tendermint-style BFT halts rather than fork during a partition, choosing consistency over availability.
What is 'MEV' (Maximal Extractable Value) related to consensus?
Answer: Value validators/miners extract by reordering, including, or censoring transactions
MEV is profit block producers can capture by controlling transaction ordering within blocks.
Why does hybrid PoW/PoS (like early Decred) combine both mechanisms?
Answer: To let stakeholders check miners, balancing security and governance
Hybrid models use PoW for block creation and PoS voting to validate them, distributing power and improving governance.