填空题 10.  When the user sends a(n) ______ request to the web server, the switch intercepts theuser's HTTP session request and presents the user with a pop-up dialog box that hasa username and password field. 用户向Web服务器发送______请求，交换机截取该请求后在用户的Web浏览器中弹出一个对话框，提示用户输入用户名和密码。