Layer 2 technology is commonly referred to as an “off chain” solution, which aims to expand the performance of blockchain while retaining the decentralized advantages of distributed protocols. In order to build a good blockchain ecosystem, we need to do something in the architecture to balance the requirements of security, decentralization, and scalability. The Layer 2 platform and protocol process data in a way that reduces the burden on the main chain, enhancing the scalability of the entire blockchain network by transferring some data processing from the main chain to Layer 2. Taking ETH as an example, the Layer 2 technology system is a system connected to Ethereum, using Ethereum as the foundation layer for security and ultimate certainty.