最新CCNA第一学期第二章答案解析
ccna第二章答案
1. Which statements correctly identify the role of intermediary devices in the network? (Choose three.)determine pathways for data 确定数据通路initiate data communicationsretime and retransmit data signals 重分发originate the flow of datamanage data flows 管理数据final termination point for data flow2. Select the statements that are correct concerning network protocols. (Choose three.)define the structure of layer specific PDU'sdictate how to accomplish layer functionsoutline the functions necessary for communications between layers limit the need for hardware compatibilityrequire layer dependent encapsulationseliminate standardization among vendors3. What are two functions of encapsulation? (Choose two.)tracks delay between end devicesenables consistent network paths for communicationallows modification of the original data before transmissionidentifies pieces of data as part of the same communicationensures that data pieces can be directed to the correct receiving end device4. What is a primary function of the trailer information added by the data link layer encapsulation?supports error detection 支持错误检测‘ensures ordered arrival of dataprovides delivery to correct destinationidentifies the devices on the local networkassists intermediary devices with processing and path selection5. Which statements correctly identify the role of intermediary devices in the network? (Choose three.)determine pathways for datainitiate data communicationsretime and retransmit data signalsoriginate the flow of datamanage data flowsfinal termination point for data flow6. What is a PDU?corruption of a frame during transmissiondata reassembled at the destinationretransmitted packets due to lost communicationa layer specific encapsulation 一个具体的封装层7. Which characteristic correctly refers to end devices in a network?manage data flowsoriginate data flow 原数据流retime and retransmit data signalsdetermine pathways for data8.Refer to the exhibit. "Cell A" at IP address 10.0.0.34 has established an IP session with "IP Phone 1" at IP address 172.16.1.103. Based upon the graphic, which device type best describes the function of wireless device "Cell A?"the destination devicean end devicean intermediate devicea media device9.Refer to the exhibit. Which three labels correctly identify the network types for the network segments that are shown?(Choose three.)Network A -- WANNetwork B -- WANNetwork C -- LANNetwork B -- MANNetwork C -- WANNetwork A -- LAN10. Which three statements best describe a Local Area Network (LAN)? (Choose three.)A LAN is usually in a single geographical area.The network is administered by a single organization.The connection between segments in the LAN is usually through a leased connection.The security and access control of the network are controlled by a service provider.A LAN provides network services and access to applications for users within a common organization.Each end of the network is generally connected to a Telecommunication Service Provider (TSP).11.Refer to the exhibit. Which networking term describes the data interleaving process represented in the graphic?pipingPDUstreamingmultiplexingencapsulation12. What is the primary purpose of Layer 4 port assignment?to identify devices on the local mediato identify the hops between source and destinationto identify to the intermediary devices the best path through the network to identify the source and destination end devices that are communicating to identify the processes or services that are communicating within the end devices13. What device is considered an intermediary device?1．file serve2.IP phone ptop 4.printer 5.switch14.Refer to the exhibit. Which term correctly identifies the device type that is included in the area B? sourceendtransferintermediary 中间设备15.Refer to the exhibit. What type of network is shown?WANMANLANWLAN16. Which layer encapsulates the segment into packets?physicaldata linknetwork 网络层封装的是数据包transport17. What can be identified by examining the network layer header?the destination device on the local mediathe destination host address 网络层头部封装目的主机的地址the bits that will be transferred over the mediathe source application or process creating the data18. What is the purpose of the TCP/IP Network Access layer?path determination and packet switchingdata presentationreliability, flow control, and error detectionnetwork media control 接入层控制网络媒体the division of segments into packets19. During the encapsulation process, what occurs at the data link layer? No address is added.The logical address is added.The physical address is added. 数据链路层添加一个物理地址The process port number is added.20.Refer to the exhibit. Which set of devices contains only end devices? A, C, DB, E, G, HC, D, G, H, I, JD, E, F, H, I, JE, F, H, I, J21. What is the proper order of the layers of the OSI model from the highest layer to the lowest layer?4physical, network, application, data link, presentation, session, transportapplication, physical, session, transport, network, data link, presentationapplication, presentation, physical, session, data link, transport, networkapplication, presentation, session, transport, network, data link, physicalpresentation, data link, session, transport, network, physical, application22. Which two layers of the OSI model have the same functions as the TCP/IP model Network Access Layer? (Choose two.)34NetworkTransportPhysicalData Link TCP/IP 工作在第一层和第二层Session。
CCNA_ERouting_Chapter_2_答案
1图中的路由器使用如图所示的子网分配。
对Router3 而言，要将内部网络通告给网云，最有效的路由总结是什么？192.1.1.0/26 和192.1.1.64/27192.1.1.128/25192.1.1.0/23 和192.1.1.64/23192.1.1.0/24192.1.1.0/25192.1.1.0/24 和192.1.1.64/242请参见图示。
要使192.168.1.0 和10.0.0.0 网络之间连通并且无需递归查找，需要使用下列哪两条命令？（选择两项。
）A (config)# ip route 10.0.0.0 255.0.0.0 s 0/1/0A(config)# ip route 10.0.0.0 255.0.0.0 172.16.40.2A (config)# ip route 10.0.0.0 255.0.0.0 s 0/0/0B(config)# ip route 192.168.1.0 255.255.255.0 s 0/0/0B (config)# ip route 192.168.1.0 255.255.255.0 172.16.40.1B(config)# ip route 192.168.1.0 255.255.255.0 s 0/1/03哪一个地址可以用来总结从172.16.0.0/24 到172.16.7.0/24 的所有网络？172.16.0.0/21172.16.1.0/22172.16.0.0 255.255.255.248172.16.0.0 255.255.252.04请参见图示。
在到达10.0.0.0 网络的路由中，/8 表示什么意思？它表示该路由器与10.0.0.0 网络之间有8 跳。
它表示发送到10.0.0.0 网络的ping 得到应答所需的时间（毫秒）。
它表示路由器可将数据包转发到带有8 个子网的目的网络。
它表示在数据包目的IP 地址中，从左开始有多少个连续比特位必须与10.0.0.0 匹配才能使用这条路由。
计算机网络与基础第二章课后习题答案.doc
填空题1、 分布在不同地理位罝的计算机，通过通信线路连接在一起2、 局域网广域网城域网3、 总新型拓扑结构星型拓扑结构扩展星型拓扑结构（物理拓扑结构）总线逻辑拓扑结构环形逻辑拓扑结构（逻辑拓扑结构） 4、 数裾分段数据的流量传输、控制 分段封装数据包实现网络之间的路由5、 所有设备程序或协议组件6、 传输控制协议 传输 数据分段流量控制为应用程序提供可靠传输服务7、 互联网协议 网络路由（路径选择）8、 地址解析协议 IP MAC控制消息 用于在IP 主机、路由器之间传递控制消息9、 数裾链路 逻辑链路控制媒体访问控制正在发送数椐 10、 信息交换 数据冲突11、 M AC 二层 路由12、 对称交换机 非对称交换机（端口带宽）桌而型交换机（端口结构）企业级交换机 二层交换机三层交换机四层交换机13、 网络层互联网络隔离网络广播路由转发防火墙14、 R OM （只读存储器） RAM/DRAM （随机访问存储器）FLASH （闪存）NVRAM（非易失性随机存取存储器）配置寄存器 INTERFACE （接口） FLASH RAM15、 隔离广播 安全管理16、 以太网 令牌环网 FDDI 网络技术 17、 10Base2 10Base5 lOBaseT 10Mbps 快速以太网 18、 总线型拓扑19、 通信线路 电路 分组电路 20、 数据链路层 数据和传输信号的转换点对点（PPP ）21、 将TE2设备的信号转换成ISDN 兼容格式的设备 基本速率接口22、 减少节点的处理时间23、 核心层汇聚层接入层24、 入门级工作组级部门级企业级 25、 4个绕对非屏蔽橙绿蓝棕26、 噪声串扰信号减弱 使电磁射线和外部电磁干扰减到最小 27、 网线制作正常线工作水平管理区垂直设备间接入*、通信资源共享正在接受数裾 固定端口交换机模块化交换机 部门级交换机工作组交换机基群速率接门2、网络协议是网络上所有设备之间通信规则的集合。
CCNA第章考试答案
C C N A第章考试答案 IMB standardization office【IMB 5AB- IMBK 08- IMB 2C】••试题反馈报告IntroductiontoNetworks(版本-ITN第1章考试以下是针对您未获得满分的试题给出的反馈。
某些交互式试题可能不显示您的答案。
1 某公司正在考虑是使用客户端/服务器还是对等网络。
下列哪三项是对等网络的特征（选择三项。
）正确响应您的响应易于创建同时充当客户端和服务器时设备性能更好可扩展安全性提升缺少集中管理实施成本更少由于不需要使用网络设备和专用服务器，对等网络易于创建，复杂性更低，且成本更少。
而且对等网络也没有集中管理。
这种网络安全性更低，不可扩展，而且那些同时充当客户端和服务器的设备可能性能更差。
此试题参考以下领域的内容：IntroductiontoNetworks•提供网络资源2 哪种设备的功能是确定消息在网际网络中传输的路径？正确响应您的响应路由器防火墙Web服务器DSL调制解调器路由器用于确定消息在网络中的传输路径。
防火墙用于过滤传入和传出的流量。
DSL调制解调器用于为家庭或组织提供Internet连接。
此试题参考以下领域的内容：IntroductiontoNetworks•网络组件3 哪两个条件有助于您从各种网络介质当中选择一种网络介质（请选择两项。
）正确响应您的响应网络上使用的终端设备的成本所选介质可以成功传送信号的距离需要优先处理的数据类型安装在网络中的中间设备的数量要安装所选介质的环境选择网络介质的条件包括：所选介质可以成功传送信号的距离、要安装所选介质的环境、必须传输的数据量和速度以及介质和安装的成本。
此试题参考以下领域的内容：IntroductiontoNetworks•网络组件4 下列哪两项描述了中间设备（选择两项。
）正确响应您的响应中间设备可以引导数据路径。
中间设备可以生成数据内容。
中间设备可以启动封装过程。
中间设备可以更改数据内容。
CCNA认证基础课程-课后作业.习题答案
CCNA认证基础-习题分析讲义第一部分第一章1. Convert the binary number 10111010 into its hexadecimal equivalent. Select thecorrect answer from the list below. （3）1) 852) 903) BA4) A15) B36) 1C2. Convert the Hexadecimal number A2 into its Base 10 equivalent. Select thecorrect answer from the list below. （4）1) 1562) 1583) 1604) 1625) 1646) 1663. Which binary number is a representation of the decimal number 248? （3）1) 111010002) 111101003) 111110004) 111110104. Which of the following will test the internal loopback of a node? （3）1) ping 10.10.10.12) ping 192.168.1.13) ping 127.0.0.14) ping 223.223.223.2235) ping 255.255.255.2555. What can be verified by successfully pinging the reserved loopback address ona host? （2）1) Connectivity exists between two hosts on the LAN.2) The TCP/IP stack of the local host is configured correctly.3) A connection exists between a host and the default gateway.4) The route a packet takes from the local host to a remote host is valid.6. Which of the following commands could be used on a Windows-basedcomputer to view the current IP configuration of the system? (Choose two.) （3，4）1) configip2) ifconfig3) ipconfig4) winipcfg5) Winipconfig7.Refer to the exhibit. What must be configured on Host B to allow it to communicate withthe Host C? (Choose three.) （2，4，6）1)the MAC address of RTA router interface connected to Switch 12) a unique host IP address3)the IP address of Switch 14)the default gateway address5)the MAC address of Host C6)the subnet mask for the LAN8. What are important characteristics to consider when purchasing a networkinterface card? (Choose two.) （2，3）1) security used on the network2) media used on the network3) system bus used on the computer4) software installed on the network5) diagnostic tools installed on the network第二章1. Select the necessary information that is required to compute the estimated timeit would take to transfer data from one location to another. (Choose two.) （1，5）1) file size2) data format3) network in use4) type of medium5) bandwidth of the link2. Using the data transfer calculation T=S/BW, how long would it take a 4MB file tobe sent over a 1.5Mbps connection? （2）1) 52.2 seconds2) 21.3 seconds3) 6.4 seconds4) 2 seconds5) 0.075 seconds6) 0.0375 seconds3. What are features of the TCP/IP Transport layer? (Choose two.) （3，5）1) path determination2) handles representation, encoding and dialog control3) uses TCP and UDP protocols4) packet switching5) reliability, flow control and error correction4. Which of the following is the Layer 4 PDU? （4）1) bit2) frame3) packet4) Segment5. What is important to remember about the data link layer of the OSI model whenconsidering Peer to Peer communication? (Choose three.) （3，4，5）1) It links data to the transport layer.2) It encapsulates frames into packets.3) It provides a service to the network layer.4) It encapsulates the network layer information into a frame.5) Its header contains a physical address which is required to complete the datalink functions.6) It encodes the data link frame into a pattern of 1s and 0s (bits) for transmissionon the medium.6. Which statement describes a star topology? （2）1) Each host in the network is connected to a backbone cable that is terminated atboth ends.2) Each host is connected to a hub or switch, either of which acts as a central pointfor all network connections.3) Each host is directly connected to two other hosts to form a long chain of hosts.4) Each host has a connection to all other hosts in the network.7. Which statements describe the logical token-passing topology? (Choose two.)（2）1) Network usage is on a first come, first serve basis.2) Computers are allowed to transmit data only when they possess a token.3) Data from a host is received by all other hosts. Electronic tokens are passedsequentially to each other.4) Token passing networks have problems with high collision rates.8. Which technologies are considered to be LAN technologies? (Choose two.) （2，5）1) DSL2) Token Ring3) Frame Relay4) ISDN5) Ethernet9.Refer to the exhibit. Host A wants to send a message to host B. Place the following stepsin the correct order so that the message can be sent. （4）A - add network layer addressesB - transmit bitsC - create application dataD - add data link layer addresses1) B, A, D, C2) D, A, C, B3) A, D, A, B4) C, A, D, B5) C, D, A, B6) C, B, A, D10.After an uns u ccessful ping to the local router, the technician decides to investigate therouter. The technician observes that the lights and fan on the router are not operational.In which layer of the OSI model is the problem most likely occurring? （4）1) transport2) network3) data link4) physical11. Refer t o the exhibit. What is the order of the TCP/IP Protocol Data Units as datais moved as indicated through the OSI model? （3）1) data, segments, frames, packets, bits2) data, packets, segments, frames, bits3) data, segments, packets, frames, bits4) data, packets, frames, segments, bits第三章1. Which combinations of charges will be repelled by electric force? (Choose two.)（4，6）1) neutral and neutral2) neutral and positive3) neutral and negative4) positive and positive5) positive and negative6) negative and negative2. Which of the following are considered the best media for use in data networkcommunications? (Choose three.) （2，3，6）1) glass2) fibers3) copper4) gold5) plastic6) silicon7) Silver3. Which of the following wireless standards increased transmission capabilitiesto 11 Mbps? （2）1) 802.11a2) 802.11b3) 802.11c4) 802.11d4. What is attenuation? （3）1) opposition to the flow of current2) measurement of electrical signals relative to time3) degradation of a signal as it travels along the medium4) amount or volume of traffic that is flowing on the medium5. Which cable specifications are indicated by 10BASE-T? （3）1) 10 Mbps transmission speed, baseband signal, 500 meter cable length, coaxialcable2) 10 Mbps transmission speed, broadband signal, 100 meter cable length, coaxialcable3) 10 Mbps transmission speed, baseband signal, 100 meter cable length,twisted-pair cable4) 10 Gbps transmission speed, broadband signal, 500 meter cable length,twisted-pair cable6. For which Ethernet installations would fiber optic rather than Cat5 UTP be abetter media choice? (Choose two.) （2，4）1) a 3 meter connection between two 10BASE-T hubs2) an environment with many potential sources of EMI and RFI3) a peer to peer connection between two NICs with RJ45 connectors4) an installation between two buildings that are located 500 meters apart5) a single building installation where installation costs are the major concern7. Refer to the exhibit. Which type of UTP cable should be used to connect Host Ato Switch1? （4）1) rollover2) console3) crossover4) straight-through8. Refer to the exhibit. Which type of Category 5 cable is used to make an Ethernetconnection between Host A and Host B? （3）1) coax cable2) rollover cable3) crossover cable4) straight-through cable第四章1. During cable testing, which of the following are used to calculate theinformation carrying capacity of a data cable? (Choose two.) （2，5）1) bit speed2) attenuation3) wire map4) saturation limit5) analog bandwidth2. What type of wiring problem is depicted in this sample of a cable tester? （3）1) a fault2) a short3) an open4) a split a good map3. In a new network installation, the network administrator has decided to use amedium that is not affected by electrical noise. Which cable type will best meet this standard? （5）1) coaxial2) screened twisted pair3) shielded twisted pair4) unshielded twisted pair5) fiber optic4. How does network cable length affect attenuation? （3）1) Category 5 cable that is run in metal conduit has the highest attenuation in theshortest distance.2) Shorter cable lengths have greater signal attenuation.3) Longer cable lengths have greater signal attenuation.4) The length of the cable has no effect on signal attenuation.第五章1. The highest capacity Ethernet technologies should be implemented in whichareas of a network? (Choose three.) （3，4，5）1) between workstation and backbone switch2) between individual workstations3) between backbone switches4) between enterprise server and switch5) on aggregate access links2. What device must be used between an AUI port of a networking device and themedia to which it is being connected? （3）1) a transducer2) a transmitter3) a transceiver4) a transponder5) a port replicator3. An ISDN Basic Rate Interface (BRI) is composed of how many signalingchannels? （1）1) 12) 23) 34) 44. Which layer of the OSI model covers physical media? （1）1) Layer 12) Layer 23) Layer 34) Layer 45) Layer 56) Layer 65. What type of network cable is used between a terminal and a console port? （3）1) cross-over2) straight-through3) rollover4) patch cable6. What is the recommended maximum number of workstations configured on apeer-to-peer network? （3）1) 252) 153) 104) 55) 27. Which of the following increases the potential for a collision to occur? （4）1) the use of an active hub instead of an intelligent hub2) the use of an intelligent hub instead of an active hub3) a reduction in the number of devices attached to the hub4) an increase in the number of devices attached to the hub8. What is the maximum length of a media segment used for 100BASE-TX? （1）1) 100 meters2) 185 meters3) 400 meters4) 500 meters9. Which cable diagram displays the end to end pinout for a crossover cable usedwith Cisco devices? （3）1) Cable A2) Cable B3) Cable C4) Cable D第六章1. What does the "10" in 10Base2 indicate about this version of Ethernet? （2）1) The version uses Base10 numbering within the frames.2) The version operates at a transmission rate of 10 Mbps.3) Frames can travel 10 meters unrepeated.4) The maximum frame length is 10 octets.2. How is a MAC address represented? （4）1) four groups of eight binary digits separated by a decimal point2) four Base10 digits separated by a decimal point3) six hexadecimal digits4) twelve hexadecimal digits5) twenty-four Base10 digits3. Which of the following statements are correct about CSMA/CD? (Choose three.)（1，3，6）1) It is a media access method used in LANs.2) It is a media access method used in FDDI WANs.3) When a device needs to transmit, it checks to see if the media is available.4) A device sends data without checking media availability because all deviceshave equal access.5) Multiple devices can successfully transmit simultaneously.6) Only one device can successfully transmit at a time.4. Which devices shown in the graphic must have a MAC address? （5）1) only PC2) only router3) PC and router4) PC, hub, and router5) PC, printer, and router第七章1. Which of the following items are common to all 100BASE technologies?(Choose three.) （1，4，5）1) frame format2) media3) connectors4) timing5) multi-part encoding2. Which of the following does 1000BASE-T use to accomplish gigabit speeds onCat 5e cable? （4）1) the use of four conductors in full-duplex mode2) the use of two multiplexed pairs of wires, simultaneously3) the use of three pairs of wires for data and the fourth for stabilization andforward error correction4) the use of all four pairs of wires in full-duplex mode, simultaneously3. For which of the following is Ethernet considered the standard? (Choose three.)（1，4，5）1) inter-building connection2) mid-length voice3) video conferencing4) vertical wiring5) horizontal wiring6) diagonal wiring4. To make sure timing limitations are not violated when implementing a 10 MbpsEthernet network involving hubs or repeaters, a technician should adhere to which rule? （4）1) the 4-5-3 rule2) the 6-4-2 rule3) the 3-4-5 rule4) the 5-4-3 rule5. What is the maximum distance that 10BASE-T will transmit data before signalattenuation affects the data delivery? （1）1) 100 meters2) 185 meters3) 300 meters4) 500 meters6. When using Category 5 UTP cable, which RJ-45 pin pairs are used to exchangedata between hosts on an Ethernet network? （2）1) 1 and 2; 4 and 52) 1 and 2; 3 and 63) 3 and 6; 7 and 84) 4 and 5; 7 and 8第八章1. John has been hired as the network administrator of a local company and hasdecided to add more hubs to the company's existing network. Which of the following has been caused by John's inexperience? （1）1) collision domain extended2) an increased number of collision domains3) increased network performance4) increased bandwidth5) extended bandwidth2. "CompA" is trying to locate a new computer named "CompB" on the network.Which of the following does "CompA" broadcast to find the MAC address of "CompB"? （2）1) MAC request2) ARP request3) ping4) Telnet5) proxy ARP3. Which of the following is a term associated with replacing hubs with switchesto increase the number of collision domains? （3）1) encapsulation2) latency3) segmentation4) layered model5) broadcast domain6) Extended4. The accumulation of traffic from which of the following can cause a networkcondition called broadcast radiation? (Choose three.) （3，5，6）1) anonymous FTP servers2) telnet sessions3) video over IP applications4) NAS services5) ARP requests6) RIP updates5. Which of the following describes the use of Spanning Tree Protocol (STP)? （4）1) resolve routing loops2) eliminate Split Horizon errors3) limit collisions4) resolve switching loops6. Which term describes the delay in time that occurs when a frame leaves itssource device and reaches its destination? （4）1) collision2) backoff3) attenuation4) latency5) broadcast7. Based on the graphic above, which of the following occurs as each host systemcomes on line in the topology? （2）1) The switch sends its MAC address to each host.2) The switch adds MAC address to the bridge table as each host sends a frame.3) Each host exchanges MAC addresses with each other.4) The switch listens for data traffic to block since the switch lacks an IP address. 8. Which devices segment collision domains? (Choose two.) （2，3）1) transceiver2) router3) switch4) hub5) media9. Which protocol is used to eliminate switching loops? （3）1) Transmission Control Protocol2) Routing Information Protocol3) Spanning Tree Protocol4) Interior Gateway Routing Protocol5) Internetworking Protocol10. Refer to the exhibit. A network associate needs to establish an Ethernetconnection between Host A and Host B. However, the distance between the two hosts is further than the cabling standards allow. Which two devices that operate at the physical layer of the OSI can be used to allow Host A and Host B to communicate? （2，5）1) switch2) hub3) bridge4) router5) repeater第九章1. Which term describes an ARP response by a router on behalf of a requestinghost? （3）1) ARP2) RARP3) Proxy ARP4) Proxy RARP2. Which protocol functions at the internet layer of the TCP/IP protocol suite? （4）1) File Transfer Protocol (FTP)2) Trivial File Transfer Protocol (TFTP)3) Transmission Control Protocol (TCP)4) Internet Protocol (IP)5) User Datagram Protocol (UDP)6) Simple Mail Transport Protocol (SMTP)3. Which of these workstation installation and setup tasks are concerned withnetwork access layer functions? (Choose two.) （2，4）1) configuring the e-mail client2) installing NIC drivers3) configuring IP network settings4) connecting the network cable5) using FTP to download application software updates4. Which part of an IP address identifies a specific device on a network? （4）1) first two octets2) third and fourth octets3) network portion4) host portion5) only the fourth octet5. Which of the following are features of the Internet Protocol (IP)? (Choose two.)（1，3）1) It is the most widely implemented global addressing scheme.2) It allows two hosts to share a single address on a local area network.3) It is a hierarchical addressing scheme allowing addresses to be grouped.4) It is only locally significant, used primarily on local area networks.6. Which of the following are useable Class A IP addresses with a default subnetmask? (Choose three.) （2，3，5）1) 127.0.39.12) 111.9.28.303) 123.1.2.1324) 128.50.38.25) 105.1.34.16) 0.23.92.37. Which application layer protocols use UDP at the transport layer? (Choose two.)（2，4）1) FTP2) SNMP3) Telnet4) DHCP5) SMTP第十章1. Which OSI layer encapsulates data into packets? （3）1) session2) transport3) network4) data link2. Which OSI layer defines the functions of a router? （3）1) physical2) data link3) network4) transport5) session3. Which of the following are Cisco proprietary routing protocols? (Choose two.)（2，6）1) RIPv22) IGRP3) OSPF4) BGP5) RIPv16) EIGRP4. A company with a Class B license needs to have a minimum of 1,000 subnetswith each subnet capable of accommodating 50 hosts. Which mask below is the appropriate one? （4）1) 255.255.0.02) 255.255.240.03) 255.255.255.04) 255.255.255.1925) 255.255.255.2245. A small company has a class C network license and needs to create five usablesubnets, each subnet capable of accommodating at least 20 hosts. Which of the following is the appropriate subnet mask? （3）1) 255.255.255.02) 255.255.255.1923) 255.255.255.2244) 255.255.255.2406. When a network administrator applies the subnet mask 255.255.255.248 to aClass A address, for any given subnet, how many IP addresses are available to be assigned to devices? （6）1) 10222) 5103) 2544) 1265) 306) 67. Host A is assigned the IP address 10.18.97.55 /21. How many more networkdevices can be assigned to this subnetwork if Host A is the only one that has an IP address assigned so far? （4）1) 2542) 5093) 10214) 20455) 40946) 81908.Refe r to the exhibit. The network administrator wants to create a subnet for thepoint-to-point connection between the two routers. Which subnetwork mask would provide enough addresses for the point-to-point link with the least number of wasted addresses?1) 255.255.255.1922) 255.255.255.2243) 255.255.255.2404) 255.255.255.2485) 255.255.255.2529. What is the correct number of usable subnetworks and hosts for the IP networkaddress 192.168.35.0 subnetted with a /28 mask?1) 6 networks / 64 hosts2) 14 networks / 32 hosts3) 14 networks / 14 hosts4) 30 networks / 64 hosts10. Which subnet masks would be valid for a subnetted Class B address? (Choosetwo.) （5，6）1) 255.0.0.02) 255.254.0.03) 255.224.0.04) 255.255.0.05) 255.255.252.06) 255.255.255.19211. Refer to the exhibit. How will the Fohi router dynamically learn routes to the192.168.16.16/28, 192.168.16.32/28, and 192.168.16.48/28 subnetworks? （3）1) with a static route2) with a routed protocol3) with a routing protocol4) with a directly connected route12. How many broadcast domains are shown in the diagram? （1）1) three2) four3) five4) six5) seven6) eight13. How many collision domains are shown in the diagram? （5）1) three2) four3) five4) six5) seven6) eight14. A router interface has been assigned an IP address of 172.16.192.166 with amask of 255.255.255.248. To which subnet does the IP address belong?1) 172.16.0.02) 172.16.192.03) 172.16.192.1284) 172.16.192.1605) 172.16.192.1686) 172.16.192.17615. Refer to the exhibit. Host A is sending data to Host B. Once R2 determines thatdata from Host A must be forwarded to R1 to reach Host B, which layer of the OSI model will R2 use to address and build the frames destined for R1?1) physical2) data link3) network4) transport5) session6) presentation16. Which type of address is 192.168.170.112/28?1) host address2) subnetwork address3) broadcast address4) multicast address17. Which type of address is 223.168.17.167/29?1) host address2) multicast address3) broadcast address4) subnetwork address18. Which combination of network id and subnet mask correctly identifies all IPaddresses from 172.16.128.0 through 172.16.159.255?1) 172.16.128.0 255.255.255.2242) 172.16.128.0 255.255.0.03) 172.16.128.0 255.255.192.04) 172.16.128.0 255.255.224.05) 172.16.128.0 255.255.255.19219. Refer to the exhibit. The internetwork in the exhibit has been assigned the IPaddress 172.20.0.0. What would be the appropriate subnet mask to maximize the number of networks available for future growth?1) 255.255.224.02) 255.255.240.03) 255.255.248.04) 255.255.252.05) 255.255.254.06) 255.255.255.0第十一章1. If a network administrator needed to download files from a remote server, whichprotocols could the administrator use to remotely access those files? (Choose two.) （3，5）1) NFS2) ASCII3) TFTP4) IMAP5) FTP6) UDP2. What is established during a connection-oriented file transfer betweencomputers? (Choose two.) （2，5）1) a temporary connection to establish authentication of hosts2) a connection used for ASCII or binary mode data transfer3) a connection used to provide the tunnel through which file headers aretransported4) a command connection which allows the transfer of multiple commands directlyto the remote server system5) a control connection between the client and server3. Which of the following protocols are used for e-mail transfer between clientsand servers? (Choose three.) （3，4，5）1) TFTP2) SNMP3) POP34) SMTP5) IMAP46) postoffice4. Which type of institution does the domain suffix .org represent? （4）1) government2) education3) network4) non-profit5. Which of the following services is used to translate a web address into an IPaddress? （1）1) DNS2) WINS3) DHCP4) Telnet6. Which part of the URL http://www.awsb.ca/teacher gives the name of thedomain? （4）1) www2) http://3) /teacher4) awsb.ca7. Which protocols are TCP/IP application layer protocols? (Choose two.) （2，4）1) UDP2) FTP3) IP4) SMTP5) TCP8. What are three characteristics of the TCP protocol? (Choose three.) （3，4，6）1) has less overhead than UDP2) is used for IP error messages3) forces the retransmission undelivered packets4) creates a virtual session between end-user applications5) carries the IP address of destination host in the TCP header6) is responsible for breaking messages into segments and reassembling9. Two peer hosts are exchanging data using TFTP. During the current session, adatagram fails to arrive at the destination. Which statement is true regarding the retransmission of the datagram? （2）1) Datagram retransmission requires user authentication.2) Datagram retransmission is controlled by the application.3) Datagram retransmission relies on the acknowledgements at transport layer.4) Datagram retransmission occurs when the retransmission timer expires in thesource host.案例学习1. 子网计算练习：Answer2. 子网号及广播地址计算练习Answer3. 子网规划练习：已知：给定一个C类地址201.16.5.0/24。
Get清风CCNA第二单元考试内容
CCNA第二单元考试内容CCNA第二单元考试内容1.STP的主要特点是什么？〔实施VLAN和中继〕a.允许架设中继，以提供冗余b.可以使交换网络的冗余最小化c.可以使错误配置和配置不一致的情况最小化d.允许在单个中继上运行几个VLAN2.STP如何选择网段上的指定端口？〔使用生成树来提高性能〕a.到根桥的开销最低路径b.到最近的非根桥的开销最高路径c.到最近的非根桥的开销最低路径d.到根桥的开销最高路径3.以下哪三种方法可以用于缓解配置问题？〔交换网络故障排除〕a.保护未使用的端口b.了解您有什么，然后开始c.保护配置。
d.验证更改，然后保存。
4.在故障排除商品访问问题时哪一个Cisco IOS 命令最有用？〔交换机网络故障排除〕a.Show controllerb.S how interfacec.Show countersd.S how run5.哪一项最好地描述了冲突域？〔了解共享LAN 的挑战〕a.试图在同一时间进行通信的两个或多个设备b.相互连接的两个网络c.共享同一带宽的网段d.以上都不时6.可以使用哪种配置模式来配置交换机上的特定端口？〔启动交换机〕a.控制器配置模式b.全局配置模式c.用户模式d.接口配置模式7.哪一项Cisco IOS命令可以正确配置交换机上的IP地址和子网掩码？〔启动交换机〕a.Ib.196.125.243.10 ip addressc.Id.I p address8.RSTP可解决哪种交换网络问题？〔使用生成树来提高性能〕a.收敛速度b.网络规模c.网络平安d.冗余拓扑9.有集线器的功能描述，哪两项是正确的？〔了解共享LAN的挑战〕a.集线器降低了冲突域的规模。
b.添加一个集线器以消除用户在网段上争用同一带宽的需求。
c.集线器可以增强数据信号，之后再重新传输。
d.集线器是一种数据链路层设备。
e.集线器可以扩展以太网LAN.10.如何通知Cisco设备解析和执行生个输入的命令？〔Cisco IOS软件的操作〕a.按Enter键b.在命令的结尾添加一个空格c.办理入命令后等待5秒钟。
思科CCNA考试答案(全)
CCNA思科考试答案（全）第 1 章考试1一家拥有10 名员工的小型公司使用单个LAN 在计算机之间共享信息。
哪种类型连接适合此公司？由当地电话服务提供商提供的拨号连接能够使公司方便且安全地连接员工的虚拟专用网络通过当地服务提供商建立的私有专用线路通过当地服务提供商提供的宽带服务（如DSL）答案：4解析：对于这种小型办公室，比较适合通过被称为数字用户线路(DSL) 的常见宽带服务实现Internet 连接，这种服务由当地的电话服务提供商提供。
由于员工人数很少，带宽的问题并不突出。
如果公司较大，在远程站点有分支机构，则专用线路会更加适合。
如果公司员工需要通过Internet 与公司联系，则采用虚拟专用网。
2哪种网络情况需要使用WAN？员工工作站需要获取动态分配的IP 地址。
员工在出差时需要通过VPN 连接到公司电子邮件服务器。
分支机构的员工需要与同一园区网络上的另一座建筑物内的公司总部共享文件。
员工需要访问托管在其建筑物内DMZ 中的公司Web 服务器上的网页。
答案：2解析：当出差的员工需要通过WAN 连接到公司电子邮件服务器时，VPN 将通过WAN 连接在员工笔记本电脑与公司网络之间创建一个安全隧道。
通过DHCP 获取动态IP 地址是LAN 通信的功能。
在企业园区的不同建筑物之间共享文件可通过LAN 基础设施来实现。
DMZ 是企业LAN 基础设施内一个受保护的网络。
3以下哪项描述了WAN 的特征？WAN 和LAN 在同一地理范围内运行，但有串行链路。
WAN 网络归运营商所有。
所有串行链路均被视为WAN 连接。
WAN 可提供到园区主干网的终端用户网络连接。
答案：2解析：WAN 可用于将企业LAN 互连到远程分支机构站点LAN 和远程工作人员站点。
WAN 归运营商所有。
虽然WAN 连接一般通过串行接口实现，但并不是所有串行链路均连接至WAN。
LAN（而非WAN）可在组织中提供终端用户网络连接。
4电路交换WAN 技术的两个常见类型是什么？（请选择两项。
(完整版)ccna1章节与期末答案
第一章：正确答案：2.4.5•解析：由于不需要使用网络设备和专用服务器，对等网络易于创建，复杂性更低，且成本更少。
而且对等网络也没有集中管理。
这种网络安全性更低，不可扩展，而且那些同时充当客户端和服务器的设备可能性能更差正确答案：1解析：正确答案： 3.5解析：选择网络介质的条件包括：所选介质可以成功传送信号的距离、要安装所选介质的环境、必须传输的数据量和速度以及介质和安装的成本。
正确答案：3和4解析：终端设备上的应用程序可以生成数据，更改数据内容并且负责启动封装过程。
正确答案：1和4解析：终端设备会发出通过网络传输的数据。
中间设备会在链路发生故障时通过备用路径传输数据，并且会过滤数据传输以增强安全性。
网络介质提供网络消息的传输通道。
正确答案：4解析：外联网是公司外部的人或企业合作伙伴访问数据的网络区域。
内部网只描述通常仅供内部人员访问的网络区域。
当设备连接到有线网络时，有线LAN 会受BYOD（自带设备）影响。
使用大学无线LAN 的设备多为平板电脑和智能手机。
大学生主要使用无线WAN 来访问他们的手机运营商网络。
.正确答案：2解析：由于通过Internet 可以联系在线供应商，所以家庭用户通过Internet 进行网上购物。
内联网基本上是仅供内部使用的局域网。
外联网是外部合作伙伴访问组织内部特定资源的网络。
家庭用户并不一定使用LAN 来访问Internet。
例如，PC 可以通过调制解调器直接连接到ISP。
正确答案：1解析：内部网这个术语用于表示一个组织的私有局域网和广域网连接。
内部网的设计旨在仅允许该组织的成员、员工或其他获得授权的人员进行访问。
正确答案：2和4解析：电缆和DSL 均能实现高带宽、始终联网，并提供到主机计算机或LAN 的以太网连接。
10正确答案：2和3解析：移动电话连接需要使用移动电话网络。
卫星连接通常用于家庭或企业外部不便使用物理布线的位置。
11正确答案：2解析：当对网络资源的请求超出了可用容量时，网络就会变得拥堵。