1. [多选题]下列哪一设备工作时，要用到OSI的七个层（一层到七层）（）
A. PC
B. 网管机
C. WEB服务器
D. 交换机
E. 路由器
2. [多选题]Ezonexam is migrating to a private IP addressing scheme. Which of the following describe the use of private IP addresses? (Choose two)
A. Addresses chosen by Ezonexam.com to communicate with the Internet.
B. Addresses that cannot be routed through the public Internet.
C. Addresses that can be routed through the public Internet.
D. A scheme to conserve public addresses.
E. Addresses licensed to enterprise or ISPs by an Internet registry organization.
3. [单选题]TCP23是（）协议端口号；UDP69是（）端口号；TCP80是（）端口号。
A. TELNET FTP HTTP
B. FTPT FTP HTTP
C. TELNET TFTP HTTP
D. TELNET DNS HTTP
4. [单选题]路由器“特权模式”的提示符是：（）
A. >
B.
C. (config)
D. (config-if)
5. [单选题]RIP协议负载均衡的路径数量为（）
A. 无限制
B. 最多4条
C. 最多5条
D. 最多6条
