What is a layer 2 quiz

Question 1

Why do layer 2 networks exist?

Accepted Answer

To scale activity cheaply while keeping the base chain secure and decentralized

Question 2

What does a rollup post to Ethereum?

Accepted Answer

Compressed batches of many transactions

Question 3

What is the key difference between optimistic and ZK rollups?

Accepted Answer

Optimistic rollups assume validity and allow fraud proofs, while ZK rollups prove validity cryptographically

Question 4

Why do standard withdrawals from an optimistic rollup take about a week?

Accepted Answer

To allow time for anyone to submit a fraud proof against the batch

Question 5

Which is a real decentralization concern with many current layer 2s?

Accepted Answer

They run a single sequencer and have upgrade keys held by a small group

What is a layer 2: the quiz