CCNA第一学期第八章答案

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思科 CCNA 学习试题答案!!!

思科 CCNA 学习试题答案思科ccna学习试题答案CCNA课程测试一、单项选择题：1.媒体100BaseT的最大传输距离为：（）a:10MB:100mc:1000md:500M2、路由器下，由一般用户模式进入特权用户模式的命令是：（）a：enableb:configc:interfaced:router3、哪个命令可以成功测试网络：()a：router>ping192.5.5.0b：router#ping192.5.5.30c：router>ping192.5.5.256d：router#ping192.5.5.2554、介质工作在osi的哪一层（）a：物理层B：数据链路层C：网络层D：传输层5。

100BaseT的速率为（）Mbit/SA:1b:10C:100D:10006、在启用igrp协议时，所需要的参数是：()a:网络掩码b:子网号c:自治系统号d:跳数7、基本ip访问权限表的表号范围是：()a:1―100b:1-99c:100-199d:800-8998、查看路由表的命令是：()a:ShowInterface B:showrunc:showiprouted:showtable9、工作在osi第三层的设备是：()a:网卡b:路由器c:交换机d:集线器10、osi第二层数据封装完成后的名称是：()a:比特b:包c:帧d:段11.为了禁止网络210.93.105.0 FTP到网络223.8.151.0并允许其他信息传输，可以实现此功能的选项有：（）a:access-list1deny210 93.105.0.0.0.0.0.0b：access-list100denytcp210.93.105.00.0.0.255223.8.151.00.0.0.255eqftpc:access-List100Permitipanyd：access-list100denytcp210.93.105.00.0.0.255223.8.151.00.0.0.255eqftpaccess-list100permitipanyany12.路由器下“特权用户模式”的标识符为：（）a:>b:！c:#d:#配置如果）#13。

思科CCNA1第八章试题及答案英文版

1. 1. QuestionWhat is a result of connecting two or more switches together?o The number of broadcast domains is increased.o The size of the broadcast domain is increased.o The number of collision domains is reduced.o The size of the collision domain is increased.2. 2. QuestionRefer to the exhibit. How many broadcast domains are there?CCNA1 v6.0 Chapter 8 Exam 005o 1o 2o 3o43. 3. QuestionWhat are two reasons a network administrator might want to create subnets?(Choose two.)o simplifies network designo improves network performanceo easier to implement security policieso reduction in number of routers neededo reduction in number of switches needed4. 4. QuestionRefer to the exhibit. A company uses the address block of 128.107.0.0/16 for its network. What subnet mask would provide the maximum number of equal size subnets while providing enough host addresses for each subnet in the exhibit?CCNA1 v6.0 Chapter 8 Exam 007o 255.255.255.0o 255.255.255.128o 255.255.255.192o 255.255.255.224o 255.255.255.2405. 5. QuestionRefer to the exhibit. The network administrator has assigned the LAN of LBMISS an address range of 192.168.10.0. This address range has beensubnetted using a /29 prefix. In order to accommodate a new building, the technician has decided to use the fifth subnet for configuring the newnetwork (subnet zero is the first subnet). By company policies, the router interface is always assigned the first usable host address and the workgroup server is given the last usable host address. Which configuration should be entered into the properties of the workgroup server to allow connectivity to the Internet?CCNA1 v6.0 Chapter 8 Exam 004o IP address: 192.168.10.65 subnet mask: 255.255.255.240, default gateway: 192.168.10.76o IP address: 192.168.10.38 subnet mask: 255.255.255.240, default gateway: 192.168.10.33o IP address: 192.168.10.38 subnet mask: 255.255.255.248, default gateway: 192.168.10.33o IP address: 192.168.10.41 subnet mask: 255.255.255.248, default gateway: 192.168.10.46o IP address: 192.168.10.254 subnet mask: 255.255.255.0, defaultgateway: 192.168.10.16. 6. QuestionIf a network device has a mask of /28, how many IP addresses are available for hosts on this network?o 256o 254o 62o 32o 16o 147. 7. QuestionWhich subnet mask would be used if 5 host bits are available?o 255.255.255.0o 255.255.255.128o 255.255.255.224o 255.255.255.2408. 8. QuestionHow many host addresses are available on the network 172.16.128.0 with a subnet mask of 255.255.252.0?o 510o 512o1022o 1024o 2046o 20489. 9. QuestionHow many bits must be borrowed from the host portion of an address to accommodate a router with five connected networks?o twoo threeo fouro five10. 10. QuestionA network administrator wants to have the same network mask for allnetworks at a particular small site. The site has the following networks and number of devices:IP phones – 22 addressesPCs – 20 addresses neededPrinters – 2 addresses neededScanners – 2 addresses neededThe network administrator has deemed that 192.168.10.0/24 is to be the network used at this site. Which single subnet mask would make the most efficient use of the available addresses to use for the four subnetworks?o 255.255.255.0o 255.255.255.192o 255.255.255.224o 255.255.255.240o 255.255.255.248o 255.255.255.25211. 11. QuestionA company has a network address of 192.168.1.64 with a subnet mask of255.255.255.192. The company wants to create two subnetworks that would contain 10 hosts and 18 hosts respectively. Which two networks wouldachieve that? (Choose two.)o 192.168.1.16/28o 192.168.1.64/27o 192.168.1.128/27o 192.168.1.96/28o 192.168.1.192/2812. 12. QuestionA network administrator is variably subnetting a network. The smallestsubnet has a mask of 255.255.255.248. How many usable host addresses will this subnet provide?o 4o 6o 8o 10o 1213. 13. QuestionRefer to the exhibit. Given the network address of 192.168.5.0 and a subnet mask of 255.255.255.224 for all subnets, how many total host addresses are unused in the assigned subnets?CCNA1 v6.0 Chapter 8 Exam 001o 56o 60o 64o 68o7214. 14. QuestionRefer to the exhibit. Considering the addresses already used and having to remain within the 10.16.10.0/24 network range, which subnet address could be assigned to the network containing 25 hosts?CCNA1 v6.0 Chapter 8 Exam 002o 10.16.10.160/26o 10.16.10.128/28o 10.16.10.64/27o 10.16.10.224/26o 10.16.10.240/27o 10.16.10.240/2815. 15. QuestionA network administrator needs to monitor network traffic to and fromservers in a data center. Which features of an IP addressing scheme should be applied to these devices?o random static addresses to improve securityo addresses from different subnets for redundancyo predictable static IP addresses for easier identificationo dynamic addresses to reduce the probability of duplicate addresses 16. 16. QuestionWhich two reasons generally make DHCP the preferred method of assigning IP addresses to hosts on large networks? (Choose two.)o It eliminates most address configuration errors.o It ensures that addresses are only applied to devices that require apermanent address.o It guarantees that every device that needs an address will get one.o It provides an address only to devices that are authorized to be connected to the network.o It reduces the burden on network support staff.17. 17. QuestionA DHCP server is used to assign IP addresses dynamically to the hosts on anetwork. The address pool is configured with 192.168.10.0/24. There are 3 printers on this network that need to use reserved static IP addresses from the pool. How many IP addresses in the pool are left to be assigned to other hosts?o 254o251o 252o 25318. 18. QuestionRefer to the exhibit. A company is deploying an IPv6 addressing scheme for its network. The company design document indicates that the subnet portion of the IPv6 addresses is used for the new hierarchical network design, with the s ite subsection to represent multiple geographical sites of the company, the s ub-site section to represent multiple campuses at each site, and thes ubnet section to indicate each network segment separated by routers. With such a scheme, what is the maximum number of subnets achievedper sub-site?CCNA1 v6.0 Chapter 8 Exam 003o 0o 4o16o 25619. 19. QuestionWhat is the prefix for the host address 2001:DB8:BC15:A:12AB::1/64?o 2001:DB8:BC15o 2001:DB8:BC15:Ao 2001:DB8:BC15:A:1o 2001:DB8:BC15:A:1220. 20. QuestionConsider the following range of addresses:2001:0DB8:BC15:00A0:0000::2001:0DB8:BC15:00A1:0000::2001:0DB8:BC15:00A2:0000::…2001:0DB8:BC15:00AF:0000::The prefix-length for the range of addresses is /6021. 21. QuestionMatch the subnetwork to a host address that would be included within the subnetwork. (Not all options are used.)CCNA1 v6.0 Chapter 8 Exam 0122. 22. QuestionRefer to the exhibit. Match the network with the correct IP address and prefix that will satisfy the usable host addressing requirements for each network. (Not all options are used.)CCNA1 v6.0 Chapter 8 Exam 006。

完整版CCNA测试题库及答案

完整版CCNA测试题库及答案描述载波侦听多路由访问/冲突检测（CSMA/CD）的工作原理。

CSMA/CD是一种帮助设备均衡共享带宽的协议，可避免两台设备同时在网络介质上传输数据。

虽然他不能消除冲突，但有助于极大的减少冲突，进而避免重传，从而提高所的设备的数据传输效率。

区分半双工和全双工通信。

并指出两种方法的需求。

与半双工以太网使用一对导线不同，全双工以太网使用两队导线，全双工使用不同的导线来消除冲突，从而允许同时发送和接收数据，而半双工可接收或发送数据，但不能同时接收和发送数据，且仍会出现冲突。

要使用全双工，电缆两端的设备都必须支持全双工，并配置成一全双模式运行。

描述MAC地址的组成部分以及各部分包含的信息。

MAC（硬件）地址时一种使用十六进制表示的地址，长48位（6B）。

其中前24位（3B）称为OUI（Organizationally Unique Idebtifier,组织唯一表示符），有IEEE分配给NIC制造商；余下的部分呢唯一地标识了NIC识别十进制数对应的二进制值和十六进制值。

用这三种格式之一表示的任何数字都可以转换为其他两种格式，能够执行这种转换对理解IP地址和子网划分至关重要。

识别以太网帧中与数据链路层相关的字段。

在以太网中，与数据链路层相关的字段包括前导码，帧其实位置分隔符，目标MAC地址，源MAC地址，长度或者类型以及帧校验序列。

识别以太网布线相关的IEEE标准。

这些标准描述了各种电缆类型的功能和物理特征，包括（但不限于）10Base2、10Base5和10BaseT。

区分以太网电缆类型及其用途。

以太网电缆分3种：直通电缆，用于将PC或路由器的以太网接口连接到集线器或交换机；交叉电缆。

用于将集线器连接到集线器，集线器连接到交换机，交换机连接到交换机以及PC连接到PC；反转电缆，用于PC和路由器或交换机之间建立控制台连接。

描述数据封装过程及其在分组创建中的作用。

数据封装指的是在OSI模型各层给数据添加信息的过程，也成为分组创建。

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。

2023年CCNA考试真题答案分析

2023年CCNA考试真题答案分析作为全球性的IT认证考试之一，CCNA（Cisco Certified Network Associate）考试一直以来都备受关注。

2023年CCNA考试的真题是许多考生关注的焦点。

下面将对2023年CCNA考试的真题答案进行分析，旨在帮助考生更好地了解考试的内容和要求。

一、第一题：在OSPF协议中，下面哪个区域是Stub区域？答案：区域0（Area 0）分析：OSPF（Open Shortest Path First）是一种广泛使用的内部网关协议（IGP）。

在OSPF中，区域被用于划分网络，Stub区域是指一个没有外部路由进入的区域。

在OSPF中，区域0通常被称为Backbone区域，是所有其他区域的集线器。

因此，区域0是Stub区域。

二、第二题：在TCP/IP协议栈中，下面哪个协议负责将IP地址转换为MAC地址？答案：ARP（Address Resolution Protocol）分析：ARP是一种用于将IP地址转换为MAC地址的协议，它工作在TCP/IP协议栈的网络层和数据链路层之间。

当一个主机需要发送数据包到目标主机时，它首先会查询ARP缓存表，如果找不到目标主机的MAC地址，则会发送ARP请求广播，请求目标主机回应其MAC地址。

三、第三题：在VLAN中，下面哪个协议用于实现不同VLAN之间的通信？答案：路由协议或三层交换机分析：VLAN（Virtual Local Area Network）是一种实现逻辑隔离的技术，可以将物理上的网络划分为多个逻辑上的网络。

不同VLAN之间的通信需要通过路由器或三层交换机来实现。

路由器可以实现不同VLAN之间的互联，而三层交换机具备路由功能，可以在交换机内部实现不同VLAN之间的通信。

四、第四题：以下哪种网络攻击会使用大量的伪造的IP数据包来淹没目标网络？答案：DDoS（Distributed Denial of Service）分析：DDoS是一种分布式拒绝服务攻击，攻击者会利用多个主机发送大量的伪造IP数据包到目标网络，造成网络堵塞、服务不可用等问题。

CCNA第一学期各章习题及答案

诶了我累了目录第二章网络通信P2-8第三章应用层功能及协议P9-14第四章OSI传输层P15-20第五章OSI网络层P21-27第六章网络编址-IPv4 P28-34第七章数据链路层P35-40第八章OSI物理层P41-45第九章以太网P46-51第十章网络规划和布线P52-61第十一章配置和测试网络P62-70第一学期末考试P71-91文档末尾返回目录第二章网络通信001 TCP/IP 网络接入层有何作用路径确定和数据包交换数据表示、编码和控制可靠性、流量控制和错误检测详细规定构成物理链路的组件及其接入方法将数据段划分为数据包002下列哪些陈述正确指出了中间设备在网络中的作用（选择三项）确定数据传输路径发起数据通信重新定时和重新传输数据信号发送数据流管理数据流数据流最后的终止点003下列哪三项陈述是对局域网(LAN) 最准确的描述（选择三项）LAN 通常位于一个地域内。

此类网络由由一个组织管理。

LAN 中的不同网段之间一般通过租用连接的方式连接。

此类网络的安全和访问控制由服务提供商控制。

LAN 为同一个组织内的用户提供网络服务和应用程序访问。

此类网络的每个终端通常都连接到电信服务提供商(TSP)。

004 什么是PDU传输期间的帧损坏在目的设备上重组的数据因通信丢失而重新传输的数据包特定层的封装005 OSI 模型哪两层的功能与TCP/IP 模型的网络接入层相同（选择两项）网络层传输层物理层数据链路层会话层006请参见图示。

所示网络属于哪一类型WANMANLANWLAN007 以下哪种特征正确代表了网络中的终端设备管理数据流发送数据流重新定时和重新传输数据信号确定数据传输路径008 第4 层端口指定的主要作用是什么标识本地介质中的设备标识源设备和目的设备之间的跳数向中间设备标识通过该网络的最佳路径标识正在通信的源终端设备和目的终端设备标识终端设备内正在通信的进程或服务009 请参见图示。

下列哪组设备仅包含终端设备A、C、DB、E、G、HC、D、G、H、I、JD、E、F、H、I、JE、F、H、I、J010 选择关于网络协议的正确陈述。

(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。

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C C N A第一学期第八章
答案
集团文件版本号：（M928-T898-M248-WU2669-I2896-DQ586-M1988）
最新CCNA第一学期第八章答案
IPv4 地址分为两个部分：网络部分 - 用于识别主机所在的特定网络，主机部分 - 用于识别网络中的特定主机。

子网掩码用于识别各个部分的长度。

定向广播是将消息发送到特定网络中的所有主机。

它适用于将广播发送到非本地网络中的所有主机。

组播消息是将消息发送到订阅组播组中的一组选定主机。

有限广播只限于将消息发送到本地网络中的主机。

单播消息是将消息从一台主机发送到另一台主机。

许多协议使用广播，因此无法避免。

路由器不转发广播，因此会在其每个接口形成一个广播域。

IPv6 中没有广播。

如果交换机收到广播数据包，它将通过除入站接口以外的所有接口转发此数据包。

6、
7、下列哪种网络迁移技术可以把 IPv6 数据包封装在 IPv4 数据包中，以便通过 IPv4 网络基础架构进行传输？
隧道迁移技术可将 IPv6 数据包封装在 IPv4 数据包中。

封装过程中会组装消息并向每一层添加信息，以便通过网络传输数据。

转换迁移技术允许支持 IPv6 的设备与支持 IPv4 的设备使用类似于 IPv4 中 NAT 的转换技术进行通信。

双堆栈迁移技术允许 IPv4 和 IPv6 协议栈在同一网络中同时共存。

组播、任播和单播属于 IPv6 地址类型。

IPv6 中没有广播地址。

环回和本地链路是单播地址的特定类型。

IPv6 全局单播地址包括三个要素。

由 ISP 提供的全局路由前缀，由组织确定的子网 ID，以及唯一标识主机接口的接口 ID。

12、支持 IPv6 的设备发送一个目的地址为 FF02::1 的数据包。

该数据包的目标是什么？
FF02::1 是本地链路范围内的全节点组播组。

所有支持 IPv6 的接口将接收和处理具有此目的地址的数据包。

13、当思科路由器从 IPv4 环境完全迁移到 IPv6 环境时，哪组命令可以正确启用 IPv6 转发和接口寻址？
ICMPv4 和 ICMPv6 通用的 ICMP 消息包括：主机确认、目标（网络、主机、协议、端口）或服务不可达、超时和路由重定向。

路由器请求、邻居请求和路由器通告是 ICMPv6 中实施的新协议。

15、当支持 IPv6 的主机需要发现预期 IPv6 目标的 MAC 地址时，源主机将在 NS 消息中使用下列哪个目的地址？
当主机需要查找目的主机的 MAC 地址时，则使用地址解析。

IPv6 主机设备将发送邻居请求 (NS) 消息到请求节点组播地址。

此地址包括两个部分，共同构成了 128 位的地址。

前半部分是 FF02::1:FF00/104，后半部分是目的主机的本地链路地址或全球单播地址的最右边 24 位。

当路由器收到一个 traceroute 数据包时，TTL 字段的值递减 1。

当该字段中的值达到零时，接收路由器不会转发数据包，并会向源发送 ICMP 超时消息。

IPv6 地址 ::1 是环回地址。

对该地址成功执行 ping 操作意味着
TCP/IP 协议栈已正确安装。

但并不意味着所有地址配置正确。