Which command will show the MAC addresses of stations connected to switch ports?（）

单项选择题QoS policies are applied on the switches of a LAN. Which type of command will show the effects of the policy in real time?（）

A. show command
B. debug command
C. configuration command
D. rommon command

单项选择题How many subnets can be gained by subnetting 172.17.32.0 23 into a 27 mask, and how many usable host addresses will there be per subnet?（）

A. 8 subnets, 31 hosts
B. 8 subnets, 32 hosts
C. 16 subnets, 30 hosts
D. 16 subnets, 32 hosts
E. A Class B address can't be subnetted into the fourth octet.

单项选择题Users have been complaining that their Frame Relay connection to the corporate site is very slow. The network administrator suspects that the link is overloaded. Based on the partial output of the Router# show frame relay pvc command shown in the graphic, which output value indicates to the local router that traffic sent to the corporate site is experiencing congestion?（）

A. DLCI = 100
B. last time PVC status changed 00:25:40
C. in BECN packets 192
D. in FECN packets 147
E. in DE packets 0

单项选择题On the network 131.1.123.0 27, what is the last IP address that can be assigned to a host?（）

A. 131.1.123.30
B. 131.1.123.31
C. 131.1.123.32
D. 131.1.123.33

单项选择题All WAN links inside the ABC University network use PPP with CHAP for authentication security. Which command will display the CHAP authentication process as it occur between two routers in the network?（）

A. show chap authentication
B. show interface serial0
C. debug ppp authentication
D. debug chap authentication
E. show ppp authentication chap