多项选择题
Which two commands correctly verify whether port security has been configured on port FastEthernet 0/12 on a switch?（）
A.SW1#show swithport port-security interface FastEthernet 0/12 B.SW1#show swithport port-secure interface FastEthernet 0/12 C.SW1#show port-secure interface FastEthernet 0/12 D.SW1#show running-config
多项选择题 下面接口为物理接口的有（）。
多项选择题 Which of the following statements are true regarding bridges and switches?（）
单项选择题 In the implementation of VLSM techniques on a network using a single Class C IP address, which subnet mask is the most efficient for point-to-point serial links（）。
