1. [单选题]Why might the Ezonexam network administrator set the configuration register to 0x2142 on a 2600 series Cisco router?
A. To boot the IOS from ROM
B. To reset the console password
C. To upload a new version of the configuration file
D. To upload a new version of the IOS
E. To allow a new memory upgrade to be recognized by the router
2. [单选题]路由器当前的模式为“端口模式”，要退回到“特权模式”，应该使用的快捷键(shortcut key)为（）
A. ctrl+b
B. ctrl+z
C. ctrl+c
D. ctrl+p
3. [单选题]关于OSPF中DR的说法不正确的是（）
A. 通过hello报文选举DR
B. 如果某路由器优先级比DR优先级高，但启动晚，它会抢占原来的DR自己成为DR
C. 一个广播类型网络中只能有一个DR
D. 一旦DR失效，BDR接替DR的工作，并重新选举一个BDR
4. [多选题]When you compare the differences between half-duplex and full-duplex Ethernet, which of the following characteristics are exclusive to half-duplex? (Select two answer choices)
A. Half-duplex Ethernet operates in a shared collision domain.
B. Half-duplex Ethernet operates in an exclusive broadcast domain.
C. Half-duplex Ethernet has efficient throughput.
D. Half-duplex Ethernet has lower effective throughput.
E. Half-duplex Ethernet operates in an exclusive collision domain.
5. [单选题]The IP network 210.106.14.0 is subnetted using a /24 mask. How many usable networks and host addresses can be obtained from this?
A. 1 network with 254 hosts
B. 4 networks with 128 hosts
C. 2 networks with 24 hosts
D. 6 networks with 64 hosts
E. 8 networks with 36 hosts
6. [单选题]要把交换机的配置文件保存到tftp服务器，应使用的命令为（）
A. copy ios tftp
B. copy running-configt ftp
C. copy flash tftp
D. copy config tftp
7. [单选题]A receiving host has failed to receive all of the segments that it should acknowledge.What can the host do to improve the reliability of this communication session?
A. Start a new session using UDP
B. Obtain a new IP address from the DHCP server
C. Use a different source port for the session
D. Decrease the sequence number
E. Decrease the window size
8. [单选题]While troubleshooting a connectivity issue from a PC you obtain the following information:Local PC IP address: 190.0.3.35/24
A. Default Gateway: 190.0.3.1
B. Remote Server: 190.0.5.250/24
C. You then conduct the following tests from the local PC:
D. Ping 127.0.0.1 - Unsuccessful
E. Ping 190.0.3.35 - Successful
F. Ping 190.0.3.1 - Unsuccessful
G. Ping 190.0.5.250 – Unsuccessful
H. What is the underlying cause of this problem?
I. TCP/IP not correctly installed
J. Local physical layer problem
K. NIC not functioning
L. Remote physical layer problem
M. None of the above
9. [单选题]A Ezonexam PC has the IP address 172.16.209.10 /22. What is the subnet of this address?
A. 172.16.42.0
B. 172.16.107.0
C. 172.16.208.0
D. 172.16.252.0
E. 172.16.254.0
10. [多选题]Using a subnet mask of 255.255.255.224, which of the IP addresses below can you assign to the hosts on this subnet? (Select all that apply)
A. 16.23.118.63
B. 87.45.16.159
C. 92.11.178.93
D. 134.178.18.56
E. 192.168.16.87
F. F. 217.168.166.192
