because more than 95% of all currency are stored on cold wallets and WAF (Web Application Firewall) is applied for a protective screen of a Web application for detecting and blocking hacker attacks.
因为超过 95% 的货币都存储在冷钱包中，而 WAF（Web 应用程序防火墙）被应用于 Web 应用程序的保护屏幕，用于检测和阻止黑客攻击。