Recently, with the active DeFi ecology on Ethereum, Ethereum's transaction processing capacity is stretched. Currently, Ethereum’s transaction fees are getting higher and higher, so that a DeFi interaction costs tens of dollars. In order to alleviate the congestion of Ethereum, Layer 2 technology is given great hope. Various Layer 2 projects have come up with solutions to alleviate the congestion problem on the Ethereum chain. These solutions can significantly reduce the execution cost of Ethereum transactions by paying a certain security or functional cost. But can Layer 2 really solve the problems of Layer 1?
Most Layer 2 projects will provide the transfer function in the second layer network, but no Layer 2 project will limit its products only to transfer services. Compared with Bitcoin, Ethereum's biggest advantage is that its smart contract platform's Turing completeness, easy development and convenient interoperability provide a powerful engine for various DApp products such as DeFi. In order to show that their Layer 2 solutions are not only helpful for transfers, most Layer 2 project parties or ecosystems are also scrambling to launch their own DeFi products. For example, Loopring launched its liquid mining product in December last year; at the same time, ZKSwap based on ZKSync was also launched on the Ethereum test network at the same time. Earlier, MCDEX, a derivatives trading platform, announced the launch of a test network on Arbitrum Rollup, the second-layer expansion plan of Ethereum.While various Layer 2 projects are successively deploying DeFi products on the second-tier network, developers are faced with the problem of choosing sides: either continue to endure high transaction fees to make products and attract users on Ethereum Layer 1, or choose a Layer 2 Develop applications in the program. Because contracts deployed in different Layer 2 projects, the asset and data circulation between them is far less convenient than Layer 1. If two DApps are deployed in different Layer 2 projects, their interaction barriers will be greatly increased. There seems to be no better way to connect them than to endure a delay of as little as a few minutes and as much as a few days to go back to Layer 1. Although there are some projects trying to provide Layer 2 interoperability solutions, these solutions essentially replace transactions with contracts before and after cross-chain (including cross-chain between Layer 1, cross-chain between Layer 2 and Layer 1, etc.), This is completely different from the Ethereum Layer 1 main network, which can run through multiple different contracts during the execution of a transaction.On the Ethereum mainnet, interacting with other contracts is as simple as calling a function. Through the interaction between contracts, various types of DeFi products can be built together like building blocks. Although some people think that the random splicing of DeFi building blocks will cause financial risks, it has to be said that it is this infinite and open interaction capability that empowers the rapid growth of DeFi in the early days and injects endless sources of innovation for smart contract applications on the blockchain , to expand the territory of the DeFi domain of the blockchain.Is the prospect brought by the Layer 2 project really what developers want? At present, the technical threshold for developing contracts in the Layer 2 project of the ZK Rollup technical route is so high that only the project party and a small number of professional developers can develop DeFi products with complex logic. And even if a professional developer with strong technology wants to realize the interoperability between contracts in Zk Rollup, it is limited by the lack of mature interaction protocol standards. For the Optimistic Rollup technology route, the compatibility with the existing contract development logic is better, and the hope of achieving interoperability within the two-layer network is higher. However, the delay time required for Optimistic Rollup to cross back to Layer 1 is much higher than that of ZK Rollup, and the interaction efficiency with Layer 1 is extremely low. Either way, the interoperability of Layer 1 Ethereum cannot be reproduced. Therefore, Ethereum with Layer 2 is not equivalent to a better-performing Ethereum, but diverts users, ecology, and funds into several independent Layer 2 circles.The non-interoperability between the second-layer projects not only split the Ethereum ecology, but also affected the early launch of the Layer 2 project, making the Layer 2 project pulled to the same starting line as the Layer 1 public chain in terms of ecological construction. And this just gives the Layer 1 public chain the possibility to join the Layer 2 battlefield.
