A team must choose between optimistic rollups and ZK-rollups for a high-frequency trading application. The application requires fast finality and low latency for withdrawals. The team has limited engineering resources and cannot afford to implement complex cryptographic systems. Which rollup should they choose, and what trade-off must they accept?

Optimistic rollup, accepting a challenge period that delays withdrawal finality.

ZK-rollup, accepting a challenge period that delays withdrawal finality.

ZK-rollup, accepting the need for complex cryptographic implementation but achieving fast finality.

Optimistic rollup, accepting the need for complex cryptographic implementation but achieving fast finality.

Which trade-off is often associated with increasing block size as a scaling solution?

Lower security due to weaker cryptography

Higher storage and bandwidth requirements for full nodes, potentially reducing decentralization

Increased transaction fees for users

Which approach is an example of on-chain scaling?

Increasing the block size limit

Using payment channels for off-chain transactions

Moving transactions to a sidechain

Batching transactions in a rollup

What is the key feature of ZK-rollups?

They use zero-knowledge proofs to validate batches without revealing transaction details

They require all transactions to be publicly visible on-chain

They use a trusted third party to validate transactions

They assume transactions are valid and use fraud proofs

EC-CouncilBlockchain Developer Certification

Domain 1Objective 7

Blockchain Scaling Solutions BDC Practice Questions (Page 11)

Part of the Blockchain Fundamentals and Architecture domain, which makes up ~14% of our current practice bank.

62questions here

13free pages

13concepts

Questions 51–55

51expert · hard
A team must choose between optimistic rollups and ZK-rollups for a high-frequency trading application. The application requires fast finality and low latency for withdrawals. The team has limited engineering resources and cannot afford to implement complex cryptographic systems. Which rollup should they choose, and what trade-off must they accept?
Select an answer first
52application · medium
A blockchain network is struggling with the scalability trilemma. The team wants to increase transaction throughput by partitioning the network so different groups of nodes process different subsets of transactions. Which solution are they implementing?
Select an answer first
53foundation · easy
Which trade-off is often associated with increasing block size as a scaling solution?
Select an answer first
54foundation · easy
Which approach is an example of on-chain scaling?
Select an answer first
55foundation · easy
What is the key feature of ZK-rollups?
Select an answer first

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Blockchain Scaling Solutions BDC Practice Questions (Page 11)

Questions 51–55

A blockchain network is struggling with the scalability trilemma. The team wants to increase transaction throughput by partitioning the network so different groups of nodes process different subsets of transactions. Which solution are they implementing?

Which trade-off is often associated with increasing block size as a scaling solution?

Which approach is an example of on-chain scaling?

What is the key feature of ZK-rollups?

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