Forks and Network Upgrades Flashcards
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Read the first 7 Forks and Network Upgrades flashcards as text
What distinguishes a User-Activated Soft Fork (UASF) from a Miner-Activated Soft Fork (MASF)?
Answer: UASF is enforced by full nodes regardless of miner support, while MASF relies on miners to signal readiness
A UASF activates based on full node enforcement on a specific date, bypassing the need for miner majority support.
During the 2017 Bitcoin scaling debate, BIP 148 was a proposal for which type of activation?
Answer: A UASF to force SegWit activation by August 1, 2017
BIP 148 specified that nodes would reject blocks not signaling SegWit support starting August 1, 2017, making it a UASF.
What is a 'velvet fork' in the context of Bitcoin protocol upgrades?
Answer: An upgrade that is backward compatible and does not split the chain even if not all nodes upgrade
A velvet fork is a protocol upgrade designed so that non-upgraded nodes can still participate without being excluded from the network.
What happened to the Bitcoin XT fork proposal in 2015?
Answer: It was abandoned after failing to gain sufficient node and miner adoption
Bitcoin XT proposed 8MB blocks but failed to achieve the 75% miner threshold needed for activation, leading to its abandonment.
In a soft fork, which group's behavior change is strictly required to enforce the new rules?
Answer: A majority of miners must enforce the new stricter rules
In a soft fork, miners enforcing the new stricter rules ensure that non-compliant blocks are orphaned, making old nodes still accept the valid chain.
What is 'chain death spiral' risk associated with hard forks?
Answer: A minority chain losing so much hash rate that block times become excessively long, making it unusable
If a minority chain retains very little hash power after a fork, difficulty adjusts slowly and blocks may take hours or days, potentially killing the chain.
Which Bitcoin Improvement Proposal introduced the concept of version bits to coordinate multiple soft fork activations simultaneously?
Answer: BIP 9
BIP 9 introduced version bits signaling, allowing miners to signal readiness for up to 29 soft forks concurrently using bits in the block version field.