CCNA（200-120）题库中英对照整理于：2015年3月31日版本：1.2声明：●本题库来源互联网（鸿鹄论坛）●本题库为英文考试原版左右选择题●中文考试为随机抽取英文题的中译版●此题库非中文考试题库，而是英文题库手动翻译●此题库为手工个人翻译，存在错误和不妥难免，不代表任何官方机构和组织●本题库旨在更好的理解英文原本题库，也可以用于中文考试参考用。
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QUESTION001Refer to the exhibit. What will Router1 do when it receives the data frame shown? (Choose three.) 参照下图，这个图示显示了Ｒ１接受到如图所示数据帧的时候会怎么做？A.Router1 will strip off the source MAC address and replace it with the MACaddress 0000.0c36.6965.Ｒ１会剥离源ＭＡＣ地址，以0000：0C36.6965代替。
B.Router1 will strip off the source IP address and replace it with the IP address 192.168.40.1. Ｒ１会剥离源IP地址，以192.168.40.1代替。
C.Router1 will strip off the destination MAC address and replace it with the MAC address0000.0c07.4320.Ｒ１会剥离源ＭＡＣ地址，以0000：0C36.6965代替。
D.Router1 will strip off the destination IP address and replace it with the IP address of 192.168.40.1.Ｒ１会剥离目的IP地址，以192.168.40.1代替。
E.Router1 will forward the data packet out interface FastEthernet0/1.R1将会从F0/1转发这个数据包。
F. Router1 will forward the data packet out interface FastEthernet0/2. R1将会从F0/2转发这个数据包数据传输过程中，IP 地址不变，但是在不同的网段中，MAC 地址要根据设备的具体情况而发生改变。
在不同网络中，依靠 IP 地址定位，在同一网络中，依靠 MAC 地址定位。
QUESTION002Refer to the exhibit. Which three statements correctly describe Network Device A? (Choose three.)如图所示，关于网络设备 A 哪三项是正确的描述？A.With a network wide mask of 255.255.255.128, each interface does not require an IP address.如果配置一个 25 位的网络号，每个端口不需要配置一个地址。
B.With a network wide mask of 255.255.255.128, each interface does require an IP address ona unique IP subnet.如果配置一个 25 位的网络号，每个端口需要配置一个地址和子网。
C.With a network wide mask of 255.255.255.0, must be a Layer 2 device for the PCs tocommunicate with each other.如果配置一个 24 位的网络号，成为一个二层设备以便让 PC 和其他设备通讯。
D.With a network wide mask of 255.255.255.0, must be a Layer 3 device for the PCs tocommunicate with each other.如果配置一个 24 位的网络号，成为一个三层设备以便让 PC 和其他设备通讯。
E.With a network wide mask of 255.255.254.0, each interface does not require an IP address. 如果配置一个 23 位的网络号，每个端口不需要配置一个地址。
QUESTION003Which layer in the OSI reference model is responsible for determining the availability of the receiving program and checking to see if enough resources exist for that communication?在 OSI 参考模型当中，哪一层可以判断程序的可用性以机是否有足够的资源来支持这个通讯？A.transport 传输层work 网络层C.presentation 表示层D.session会话层E.application应用层QUESTION004Which of the following describes the roles of devices in a WAN? (Choose three.)下列哪些描述广域网设备的作用？A. A CSU/DSU terminates a digital local loop 联系数字本地环路B. A modem terminates a digital local loopC. A CSU/DSU terminates an analog local loopD. A modem terminates an analog local loop 一个模拟信号F. A router is commonly considered a DTE device路由器通常是 DTE 设备G. A router is commonly considered a DCE device路由器通常是 DCE 设备QUESTION005Refer to the exhibit, Host A pings interface S0/0 on router 3, what is the TTL value for that ping? 如图所示，主机 A 的 ping 路由器 3 的 S0/0 接口，TTL 值会是多少？A.253B.252C.255D.254QUESTION006A network administrator is verifying the configuration of a newly installed host by establishing an FTP connection to a remote server. What is the highest layer of the protocol stack that the nework administrator is using for this operation?网络管理员验证的配置是一个新安装的主机通过建立 FTP 连接到远程服务器。
网络管理员这个操作使用的最高协议层是什么？A.applicationB.presentationC.sessionD.transportE.internetF.data linkFTP 协议属于应用层QUESTION007Refer to the exhibit. After HostA pings HostB, which entry will be in the ARP cache of HostA to support this transmission?如图所示，主机Ａping 主机 B，在此通信中，以下哪个列表将会进入主机 A 的 ARP 缓存？A.B.C.D. E.F.QUESTION008A network interface port has collision detection and carrier sensing enabled on a shared twisted pair network. From this statement, what is known about the network interface port?在一个双绞线网络中的一个网络接口上监测到网络冲突，冲这个表述中，有关这个网络接口，哪一项是正确的？A.This is a 10Mb/s switch port.B.This is a 100Mb/s switch port.C.This is an Ethernet port perating at half duplex.D.This is an Ethernet port operating at full duplex.E.This is a port on a network interface card in a PC.半双工模式会产生冲突，全双工模式不会产生冲突QUESTION009A receiving host computes the checksum on a frame and determines that the frame is damaged.The frame is then discarded.At which OSI layer did this happen?收到一个主机发来的帧并进行校验以确认是否损坏，然后丢弃。
这个过程在 OSI 哪一层发生？A.sessionworkC.PhysicalD.data linkE.Transport传输层：数据段，segment网络层：数据包，数据报，packet数据链路层：数据帧，frameQUESTION010Which of the following correctly describe steps in the OSI data encapsulation process? (Choose two.)以下那些正确描述了 OSI 数据封装的过程？A.The transport layer divides a data stream into segments and may add reliability and flowcontrol information.传输层将数据分段，并且加上可靠性和流控制信息。
