Please explain the inner workings of ZK Rollups and Optimistic Rollups and compare the differences between these rollup structures. Additionally, explain the differences between ZK Rollups, Volition, and Validium modes. (5 pt)
According to L2 Beat, there are multiple stages for a Layer 2. What are the criteria for each stage, and what is the current status of the Layer 2 solutions in use? (5pt)
Layer 2 solutions aim to address scaling issues in the Ethereum ecosystem, but they introduce liquidity fragmentation, which leads to interoperability challenges. Cross-chain bridges can help address these issues. Modern cross-chain bridges can be categorized into burn-and-mint, lock-and-mint, and lock-and-unlock mechanisms. Please analyze two cross-chain bridge structures (e.g., LayerZero, Wormhole and more) with distinct underlying mechanisms. (5 pt)
Cross-chain bridges have suffered significant losses due to security breaches. For example, in 2021, PolyNetwork experienced a $611 million exploit, BNB Bridge faced a $586 million exploit, and Wormhole was attacked for $326 million. Please analyze the vulnerabilities in a cross-chain bridge structure, providing code examples to illustrate the issues. (5 pt)
User experience is key to the mass adoption of blockchain. Currently, intent-based solutions are popular. What is an intent, and how does it differ from a cross-chain bridge? (5 pt)
The ongoing bull market is marked by an increase in both the number and total losses from phishing scams. Please explain how permit and permit2 work, along with examples of phishing scams related to these operaitons. (5 pt)