From the perspective of asset control, in CEX, user assets are controlled by the platform, and users need to transfer their assets to the wallet of the trading platform. The asset custody function of the centralized trading platform is just like a bank. The user deposits the money in the bank, and the bank gives the user an account to record the user’s funds. The bank has absolute control over the user’s funds; on ZKSwap, the user’s assets are completely in the control of the user. ZKSwap does not provide fund custody services, so it cannot control or transfer users' funds. As a decentralized exchange in Layer-2, ZKSwap has passed the security audits of three major audit institutions (ABDK, Certik, and SlowMist) for its contracts and circuit codes. Users control their own private keys and their assets are safe and controllable.