TP Courses 18 — Layer 2 Scaling Solutions: Rollups

The last solution we’ll introduce is Rollup, which is recognized as the best Layer 2 solution currently. There are two apporoaches about Rollups: ZK Rollup (ZKR) and Optimistic Rollup (OR)

ZK Rollup (ZKR)
ZK Rollup uses cryptographic zero-knowledge proofs to ensure the security of the network and data. ZK Rollup separates calculation and verification. Funds are held by smart contracts on the main chain, and calculations and storage are performed on the off-chain. Through each Rollup block, a zero-knowledge proof of state transition is generated and verified with the main chain contract to achieve higher throughput and a reduction in transaction costs.

Advantages:
Fast speed
High security
Suitable for payment and DEX

Disadvantages:
RAM and CPU consumption
Low smart contract compatibility

Applications: Loopring、Hermez、Matter Labs 、 Starkware

Optimistic Rollup (OR)
Optimistic Rollup is compatible with the Ethereum Virtual Machine (EVM) and is very convenient to the migration of Ethereum DApps. Optimistic Rollup uses the fraud proof in the game mechanism to ensure its security. Drawing on Plasma and ZKR, the fraud proof also have a one-week “challenge period”, which will reduce the efficiency of capital utilization.

Advantages:
Compatible with EVM
Support common smart contracts
High security

Disadvantage:
Due to the “challenge period” mechanism, the capital utilization rate is affected by the long waiting period.

Applications: Arbitrum、Optimism、Fuel labs