思科CCNA第一学期第8章答案

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思科题目

CCNACCNA11章节考试题之01《生活在以网络为中心的世界》1、在主要使用文本相互通信的两人或多人之间，他们使用的哪种通信形式属于基于文本的实时通信？A.网络日志B.维基C.即时消息D.播客E.协作工具2、哪种网络为客户提供对企业数据（如库存、部件列表和订单）的有限访问？A.内部网B.外联网C.网际网络D.Internet3、出于管理数据的目的，需要使用什么来权衡通信的重要性及其特征？A.网络管理B.网络流量C.QoS策略D.网络评估4、对网络通信采取哪些处理后才能使服务质量策略正常发挥作用？（选择两项）A.根据服务质量要求对通信分类。

B.对应用程序数据的每个分类分配优先级。

C.始终对Web通信分配高优先级处理队列。

D.始终对数字电影分配高优先级处理队列。

E.始终对电子邮件通信分配低优先级队列。

5、网络体系结构有哪两个部分？（选择两项）A.构成以人为本网络的人B.通过网络传输消息的编程服务和协议C.通过网络传输的数据D.支持网络通信的技术E.运营和维护数据网络的企业6、在当初开发Internet时，放弃面向连接的电路交换技术出于哪三个原因？（选三项）A.电路交换技术要求将单个消息划分为包含编址信息的多个消息。

B.早期的电路交换网络在电路出现故障时不能自动建立备用链路。

C.电路交换技术要求即使两个位置之间当前并未传输数据，也必须在网络端点之间建立开放电路。

D.通过面向连接的电路交换网络传输消息无法保证质量和一致性。

E.建立多路并发开放电路获得容错能力成本高昂。

7、开发Internet时使用数据包交换无连接数据通信技术出于哪三个原因？（选三项）A.它能快速适应数据传输设施的丢失。

B.它能有效利用网络基础架构传输数据。

C.数据包可同时通过网络采取多条路径传输。

D.支持按建立连接的时间收取网络使用费用。

E.传输数据之前需要在源设备和目的设备之间建立数据电路。

8、QoS在融合网络中的作用是什么?A.确保丢弃高于可用带宽水平的所有通信B.确定网络中不同通信的传输优先级C.针对所有网络通信确定精确的优先级D.允许网络中的其它组织共享未使用的带宽9、将左侧的选项和右侧的对象连线，使网络体系结构的特征与其定义相匹配。

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。

思科网院-网络工程-CCNA1-2017计算机科学与技术-一到十一章-题库及答案

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。

）哪种设备的功能是确定消息在网际网络中传输的路径？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。

）下列哪两项描述了中间设备？（选择两项。

）网络上的终端设备有哪两项功能？（选择两项。

）由于许多学生带着自己的平板电脑和智能手机去学校访问学校资源，大学里的IT 人员最有可能需要重新设计的网络区域是什么？家庭用户必须要有哪种网络类型访问才能进行网上购物？一位分支机构办公室的员工正在为客户创建报价。

为此，该员工需要访问位于总部办公室的内部服务器上的机密定价信息。

该员工将要访问哪种类型的网络？下列哪两种连接选项可以为家庭办公室中的计算机提供始终在线的高带宽Internet 连接？（选择两项。

）下列哪两个Internet 连接选项不需要建筑物铺设物理电缆？（请选择两项。

）以下哪种术语描述了当对网络资源的请求超出可用容量时网络的状态？哪种类型的网络流量需要QoS？以下哪项表述准确定义了术语“带宽”？网络管理员正在实施一种要求复杂强密码的策略。

该策略支持哪种数据保护目标？下列哪种说法正确描述了云计算的特征？什么是Internet？下列哪种说法描述了电力线网络技术的用途？哪种安全侵犯会对家庭用户的生活造成最大损害？一位用户正在一个小型办公室网络上实施安全策略。

以下哪两种操作将为此网络提供求？（选择两项。

）A网络能够通过相同的通信通道传输语音、视频、文本和图形。

填空题。

缩写词是指允许员工在公司办公室中使用其个人设备访问网络和其他资源的策略。

正确答案：byod将每个描述与网络通信形式配对请将每个特征对应的internet连接类型进行匹配将每个定义与安全目标配对操作软件内核的作用是什么？网络管理员与交换机建立远程CLI 连接对其实施管理时，需要确保用户ID、密码和会话内容的保密性。

应当选择哪种访问方法？当在安全环境下执行初始配置时，下列哪个程序可用来访问Cisco 2960 交换机？哪个命令或组合键让用户返回命令层级中的上一级？某台路由器具有有效的操作系统，且NVRAM 中存储有配置文件。

思科 cisco 课后习题答案

在网络园区中接入层通常由lan交换设备组成这些设备的端口可用于连接工作站和服在wan环境中接入层让远程工作人员或远程站点能够使用wan技术访问公司网络
附录
检查你的理解和较难的问题和练习答案
第1章
检查你的理解
1．B、C、E 以太网交换机和转发器通常用于 LAN 中。路由器可视为 LAN 设备和 WAN 设备，用于在公司网络内部路由分组、将分组路由到 ISP 以及在自主系统之间路由分组。接入服务器集中拨入和拨出的用户通信，它可能有模拟和数字接口，可支持数百名用户同时连接到提供商的 WAN。 2．D 3．电路交换：D 分组交换：C 面向连接的分组交换：B 无连接的分组交换：A 4．城域以太网：A X.25：D ATM：B 帧中继：C 5．C DTE 通过 WAN 传输来自客户网络或主机计算机的数据。DTE 通过 DCE 连接到本地环路。路由器是一种 DTE 设备，它使用 CSU/DSU（DCE 设备）连接到 WAN。 6．E 租用线是一种专用的点到点链路，通常是向运营商租用的。 7．DLCI 唯一地标识了帧中继虚电路，这确保 DTE 设备之间能够进行双向通信。 8．异步传输模式（ATM）技术可通过私有和公共网络传输语音、视频和数据，它是建立在基于信元的架构而不是基于帧的架构的基础之上的。 9．C 10．B 11．C 12．E 13．C 14．C 15．C Cisco 企业分支机构架构让能够将园区网中的应用程序和服务延伸到各种远程位置和用户，接入层用于将用户连接到网络，这层通常使用第 2 层和第 3 层交换机。在北美，ISDN PRI 包含 23 个 64kbit/s 的 B 信道和 1 个 64kbit/s 的 D 信道，总比特率高 VPN 使用隧道通过公共网络（如 Internet）在两个私有网络之间安全地传输数据。分布层将工作组放在不同的网段中，从而隔离子网或 VLAN 中的网络问题。VLAN 之间本地环路将用户驻地的 CPE 连接到服务提供商的 CO，有时也被称为“最后一公里” 。企业远程工作人员架构让雇员能够远程（通常是从家里）连接到网络。而不管其规模和位置如何。核心层也称为网络主干，设计用于尽可能快地交换分组。

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。

思科CCNA考证习题答案

1. what could be possible causes for the "Serial0/0 is down"interface status? 这可能是为“Serial0 / 0的可能原因是向下”接口的状态？TWOA.a layer 1 problem exists.1层存在问题D.an incorrect cable is being used。

2.before installing a new,upgraded version of the ios,what should be checked on the router,and which command should be used to gather this information?在安装一个新的，升级的IOS版本，应该怎样检查路由器上，并命令应该被用来收集这些资料？B.the amount of avaiable flash and ram 缴费的闪存和RAM的数量D.show version 显示版本3.refer to the exhibit. which two statements are true about inter VLAN routing in the topology that is shown in the exhibit?（choose two）指展览。

这两个语句是对国际米兰的是在展会上展出的拓扑路由的VLAN是否属实？D. the FastEthernet 0/0 inerface on router1 must be configured with subinterfaces.关于路由器1的在FastEthernet 0/0 inerface 必须配置子接口F.the FastEthernet 0/0 interface on router1 and switch2 trunk ports must be configured using the same encapsulation type. 对在FastEthernet 0/0 接口上路由器1和交换器2中继端口必须配置使用相同的封装类型。

CCNA1复习资料

第二章网络通信2.3.1通信要素：a：消息来源，或发送方b：目的地，或消息接收方C：通道2.3.0 传送消息1:分段消息：优点：多路复用（发生在多个分段能互相融合共用一条共享介质时）增强网络通信的效率2.3.3网络的组成部分物理要素：设备和介质2.3.4终端设备及其在网络中的作用主机和终端设备：●计算机●网络打印机●V oIP电话●网络照相机（Web摄像头和安全摄像头）●移动手持设备●用于气象观测的遥控站2.3.5中间设备功能：●重新生成和重新传送数据信号●维护有关网络和网际网络中存在那些通道的信息●将错误和通信故障通知其他设备●发生链路故障时按照备用路径转发数据●根据QOS优先级别分类和转发消息●根据安全设置允许或拒绝数据通行2.3.6网络介质类型：铜缆光缆无线选择网络介质考虑的因素：介质可以成功传送信号的距离要安装介质的环境用户需要的带宽安装的费用连接器与兼容设备的费用2.4局域网·广域网·网际网络2.4.1局域网（LAN）局域网是一组终端设备和有共同的组织管理的用户2.4.2广域网（W AN）连接分布于不同地理未知的LAN的这些网络称为广域网2.4.4网络表达方式网络接口卡（NIC）物理端口接口2.5 协议定义：协议是任何人与其他人进行通信时使用的规则协议族：协同工作保证通信成功的规则或协议被组成定义内容：A·消息的格式B·中间设备共享到达目的地路径信息的方法C·在中间设备之间处理更新消息的方法D·在主机间发起和终止通信的过程标准化网络协议组织：A·电气电子工程师协会（IEEE ）B·Internet工程任务组（IETF）协议的类型：A·超文本传输协议（HTTP）:控制Web服务器和Web客户端进行交互的方式B·传输控制协议（TCP）:用于管理Web服务器和Web客户端之间单个会话的传输协议C·网间协议:最常用的网间协议是网际协议IPD·网络访问协议:描述数据链路管理和介质上的数据的物理传输两项主要功能2.6 分层模型优点：●定义通用的术语来描述网络的功能●将出来分段，允许发展执行某一功能的技术独立于执行其他功能的技术●促进竞争●提供了描述网络功能和能力的通用语言●有助于协议设计模型：OSI模型TCP/IP模型应用层应用层表示层会话层传输层传输层网络层网际层数据链路层网络接口层物理层TCP/IP模型功能应用层：为用户表示应用数据传输层：支持设备间的通信和执行错误纠正网际层：确定通过网络的最佳路径网络接口层：控制网络的硬件设备和介质通信的过程●A·在发送方源终端设备的应用层创建数据●B·当数据在源终端设备中沿协议族向下传递时对其分段和封装●C·在协议族网络接口层的介质上生成数据u●D·通过有介质和任意中间设备组成的网际网络传输数据●E·在目的终端设备的网络接口层接收数据●F·当数据在目的设备中沿协议族向上传递时对其解封装和重组●G·将此数据传送到终端设备应用层的目的应用程序2.6.5 协议数据单元和封装●封装：对数据经过分层模型是加入控制通信的过程●解封装：去掉多余的信息并且只将原始的数据发送给目标应用程序协议数据单元名PDU名层PDU名层数据应用层PDU 帧网络接口层PDU 数据段传输层PDU 比特(位) 通过介质实际传输数据是使用的PDU 数据包网际层PDUISO模型功能：A·应用层：为终端用户提供应用程序服务B·表示层：为应用提供数据C·会话层：在用户间管理会话D·传输层：在源定义数据段并编号E ·网络层：为能通过其他网络上的中间设备进行端到端的发送建立和编址包F·数据链路层：为在局域网上的主机或广域网的设备间的发送建立和编址帧G·物理层：在设备间传送比特数据。

2016CCNA1各章及期末考试答案

ITN 第7 章考试1什么是套接字？正确响应您的响应源和目的IP 地址以及源和目的以太网地址的组合源IP 地址与端口号的组合或目的IP 地址与端口号的组合源和目的序列号和确认号的组合源和目的序列号和端口号的组合套接字是源IP 地址与源端口号的组合，或者目的IP 地址与目的端口号的组合。

此试题参考以下领域的内容：Introduction to Networks•7.1.2 TCP 和UDP 简介2主机设备需要通过网络发送大型视频文件，同时为其他用户提供数据通信。

下列哪种功能可以让不同通信流同时发生，而不会让一个数据流使用所有可用带宽？正确响应您的响应窗口大小多路复用端口号确认多路复用对交替发送多个通信流很有用。

窗口大小用于降低数据通信速率。

端口号用于将数据流传送到正确的应用程序。

确认用于通知发送设备数据包流已收到或未收到。

此试题参考以下领域的内容：Introduction to Networks•7.1.1 数据传输3主机设备通过HTTP 协议向Web 服务器发送数据包。

传输层使用下列哪项来将数据流传送到服务器上的正确应用程序？正确响应您的响应序列号确认源端口号目的端口号目的端口号用于将数据流传输到正确的应用程序，而源端口号由源设备随机生成并进行跟踪。

序列号用于指示如何重组和重新排序收到的数据段。

确认用于通知发送设备数据包流已收到或未收到。

此试题参考以下领域的内容：Introduction to Networks•7.1.1 数据传输4UDP 传输协议有什么有利功能？正确响应您的响应确认已接收的数据减少传输延迟使用序列号跟踪数据段能够重新传输丢失的数据由于其报头小于TCP 报头，UDP 协议可以减少传输延迟。

此试题参考以下领域的内容：Introduction to Networks•7.1.1 数据传输5下列哪种场景描述了传输层提供的功能？正确响应您的响应学生使用教室里的VoIP 电话给家里打电话。

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。

思科答案CCNA4-8

1.逻辑网络图中一般含有哪两项信息？（选择两项。

）34电缆类型连接器类型接口标识符虚电路的DLCI操作系统版本2.广播流量过多一般表明哪一层出了问题？2物理层数据链路层网络层传输层3.下列哪项是物理层故障的例子？4封装不正确STP 配置不正确ARP 映射不正确时钟频率不正确4.当建立网络基线时必须考虑哪两项因素？（选择两项。

）15关于网络设计的信息网络中的IP 地址分配情况关于服务提供商设置的要求关于用于规范流量的访问控制列表的要求正常工作条件下的预期性能5.请参见图示。

在创建网络文档的过程中应该进行哪两个步骤？（选择两项。

）23记录仅在园区网络中发现的设备的相关信息。

记录在整个网络中（包括远程站点）发现的设备的相关信息。

将网络配置表中与拓扑图所示组件相关的任何设备信息记录下来。

仅将网络配置表中与拓扑图所示组件相关的第2 层和第3 层设备信息记录下来。

将网络配置表中与拓扑图所示组件相关的在网络使用高峰期收集的的设备信息记录下来。

6.下列关于逻辑网络模型的说法中哪两项正确？（选择两项。

）26TCP/IP 将OSI 模型的最低层划分为两个相互独立的层。

TCP/IP 模型的顶层综合了OSI 模型的上面三层的功能。

使用TCP/IP 模型进行故障排除所需的技术与使用OSI 模型时不同。

网络接入层负责在TCP/IP 网络中的设备之间交换数据包。

Internet 层负责在处于不同主机上的应用（例如FTP、HTTP 和SMTP）之间提供通信。

TCP/IP 网络接入层对应于OSI 物理层和数据链路层。

7.全公司的各个客户端报告数据中心内运行的所有企业应用程序性能均不良，而Internet 接入以及企业WAN 中运行的应用程序均工作正常。

网络管理员使用协议分析器观察到数据中心内应用程序服务器LAN 中持续存在随机无意义的流量广播(jabber)。

管理员应该如何开始故障排除过程？1 数据中心中的超时传输现象表明存在本地物理层问题。

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。

思科第一学期第8章测试答案

1 Which type of cable run is most often associated with fiber-optic cable?**backbone cablehorizontal cablepatch cablework area cable2 In most business LANs, which connector is used with twisted-pair networking cable?BNCRJ-11**RJ-45Type F3 When is a straight-through cable used in a network?when connecting a router through the console portwhen connecting one switch to another switch**when connecting a host to a switchwhen connecting a router to another router4 With the use of unshielded twisted-pair copper wire in a network, what causes crosstalk within the cable pairs?**the magnetic field around the adjacent pairs of wirethe use of braided wire to shield the adjacent wire pairsthe reflection of the electrical wave back from the far end of the cablethe collision caused by two nodes trying to use the media simultaneously5 Which OSI layer is responsible for binary transmission, cable specification, and physical aspects of network communication?PresentationTransportData Link**Physical6 An installed fiber run can be checked for faults, integrity, and the performance of the media by using what device?light injector**OTDRTDRmultimeter7 XYZ Company is installing new cable runs on their data network. What two types of cable would most commonly be used for new runs? (Choose two.)coaxCat4 UTP**Cat5 UTP**Cat6 UTPSTP8 What is a possible effect of improperly applying a connector to a network cable? Data will be forwarded to the wrong node.**Data transmitted through that cable may experience signal loss.An improper signaling method will be implemented for data transmitted on that cable.The encoding method for data sent on that cable will change to compensate for the improper connection.9 What are three measures of data transfer? (Choose three.)**goodputfrequencyamplitude**throughputcrosstalk**bandwidth10Refer to the exhibit. Which type of Category 5 cable is used to make an Ethernet connection between Host A and Host B?coax cablerollover cable**crossover cablestraight-through cable11 In LAN installations where potential electrical hazards or electromagnetic interference may be present, what type of media is recommended for backbone cabling?coax**fiberCat5e UTPCat6 UTPSTP12 Which fiber connector supports full duplex Ethernet?13 Which method of signal transmission uses radio waves to carry signals? electricaloptical**wirelessacoustic14 Which characteristics describe fiber optic cable? (Choose two.)**It is not affected by EMI or RFI.Each pair of cables is wrapped in metallic foil.It combines the technique of cancellation, shielding and twisting to protect data. It has a maximum speed of 100 Mbps.**It is the most expensive type of LAN cabling.15 Which of the following is a characteristic of single-mode fiber-optic cable? generally uses LEDs as the light sourcerelatively larger core with multiple light pathsless expensive than multimode**generally uses lasers as the light source16 What is considered a benefit of wireless as a media choice?**more host mobilitylower security risksreduced susceptibility to interferenceless impact of the surroundings on the effective coverage area17 What characteristic of UTP cable helps reduce the effects of interference?the metal braiding in the shieldingthe reflective cladding around core**the twisting of the wires in the cablethe insulating material in the outer jacket18 What is a primary role of the Physical layer in transmitting data on the network? **create the signals that represent the bits in each frame on to the mediaprovide physical addressing to the devicesdetermine the path packets take through the networkcontrol data access to the media。

思科8章练习答案

下列哪一术语用于边界路由器与防火墙之间的公共网络？“清洁的”LAN内部网DMZ外联网***学生答案无法显示，因为没有提交答案。

一家公司想配置防火墙监控所有通信通道，同时只允许属于已知连接的流量通过。

应部署哪种包过滤代理状态包侦测无状态包侦测***学生答案无法显示，因为没有提交答案。

某个黑客已获取访问敏感网络文件的权限。

通过对此攻击进行分析，发现该黑客通过网络的无线部分获取该无线网络上仅设置有一个安全措施，就是MAC 地址过滤。

该黑客很可能是怎样获取网络访问权限的黑客使用软件工具破解了共享的十六进制密钥。

黑客获取了一个可以访问主机的MAC 地址，然后克隆到他的无线笔记本电脑网卡上。

黑客发起了一个拒绝服务攻击，攻破防火墙之后进入无线LAN。

黑客获取了无线访问MAC 地址数据库的权限，然后将他自己的MAC 地址添加到允许地址列表。

***学生答案无法显示，因为没有提交答案。

使用WPA 保护无线网络有何优点？使用128 位预共享十六进制密钥阻止未经授权的无线访问。

使用不会在主机和访问点之间传输的高级加密密钥可以在旧式无线硬件上使用，因此可以为企业设备提供最大的兼容性。

请求无线访问的网络设备MAC 地址必须处于认可的MAC 地址里。

***学生答案无法显示，因为没有提交答案。

关闭窗口SNMP 使用什么来存储收集到的网络信息？网络管理站网络管理数据库管理信息库数据库信息代理***学生答案无法显示，因为没有提交答案。

SNMP 网络代理使用哪种通信机制向网络管理站提供重要但未经请求的信息？查询广播ICMP ping陷阱轮询***学生答案无法显示，因为没有提交答案。

哪三个协议用于带内管理？（选择三项。

）FTPHTTPSNMPTelnetTFTPDHCP***学生答案无法显示，因为没有提交答案。

syslog 客户端生成并转发到syslog 服务器的日志消息中通常包含哪三个项目？（选择三项。

）消息的日期和时间发送设备的ID消息的长度消息ID校验和字段社区ID***学生答案无法显示，因为没有提交答案。

(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。

思科网络学院网络安全(CCNA ) - CCNAS 第8章)

使用VPN 确保私有数据传输需要哪种技术？可扩展性虚拟化加密授权2哪种类型的站点间VPN 使用受信任组成员来消除组成员之间的点到点IPsec 隧道？GREDMVPNMPLSGETVPN3必须允许哪三个协议通过公司防火墙，以建立IPsec 站点间VPN？（选择三项。

）NTPHTTPSAHISAKMPESPSSH4NAT-T 的目的是什么？当VPN 的一端或两端使用NAT 时允许VPN 正常工作允许为IPv6 地址使用NAT为基于PC 的VPN 客户端启用NAT为IPv4 升级NAT 请参见图示。

路由器如何处理与访问列表101 定义的流量不匹配的流量？它将以未加密的方式发送。

它将被丢弃。

它将被加密发送。

它将被阻止。

导航条6以下哪两项是对IPsec 特征的准确描述？（选择两项。

）IPsec 在网络层运行，并涵盖所有第2 层协议。

IPsec 在传输层工作，并保护网络层的数据。

IPsec 是依赖于现有算法的开放标准框架。

IPsec 在应用程序层工作，并保护所有应用程序数据。

IPsec 是依赖于思科特定算法的专有标准框架。

IPsec 是思科开发的标准框架，依赖于OSI 算法。

7下列哪项是对VPN 的正确描述？VPN 使用开源虚拟化软件通过互联网创建隧道。

VPN 使用虚拟连接通过公共网络创建专用网络。

VPN 使用专用物理连接在远程用户之间传输数据。

VPN 使用逻辑连接通过互联网创建公共网络。

8在创建IPsec 隧道时，定义需要关注的流量需要什么？访问列表散列算法安全关联转换集9如果使用IPsec VPN 隧道连接两个站点，何时会创建安全关联(SA)？仅在第1 阶段期间在第1 阶段和第2 阶段都创建仅在第2 阶段期间创建隧道后，发送流量之前导航条10下列哪个术语描述了接口接收的VPN 流量被路由回同一接口的情况？拆分隧道发夹(Hairpinning)MPLSGRE11请考虑思科ASA 上的以下配置：crypto ipsec transform-set ESP-DES-SHA esp-des esp-sha-hmac此命令的用途是什么？定义用于建立隧道的ISAKMP 参数定义用于构建IPsec 隧道的加密和完整性算法仅定义允许的加密算法定义允许通过隧道且受隧道保护的流量导航条12 请参见图示。

CCNA第一学期各章习题和参考答案.doc

CCNA第一学期各章习题和参考答案第二章网络通信1、TCP/IP网络接入层有何作用？A路径确定和数据包交换B数据表示、编码和控制C可靠性、流量控制和错误检测E将数据段划分为数据包2、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）B发起数据通信D发送数据流F数据流最后的终止点3、下列哪三项陈述是对局域网(LAN) 最准确的描述？（选择三项）C LAN 中的不同网段之间一般通过租用连接的方式连接。

D此类网络的安全和访问控制由服务提供商控制。

F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？A传输期间的帧损坏B在目的设备上重组的数据C因通信丢失而重新传输的数据包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）018哪个应用层协议通常用于支持客户端与服务器之间的文件传输？A HTMLB HTTP D Telnet019哪个应用层协议中规定了Microsoft 网络中用于文件共享的服务？A DHCPB DNS D SMTP E Telnet020服务器上的应用层通常如何处理多客户端服务请求？A终止与服务的所有连接B拒绝与单一守护程序的多个连接C暂停当前连接，建立新连接第四章OSI传输层001下列哪两项是用户数据报协议(UDP) 的功能？（选择两项）A流量控制 D 面向连接E 序列和确认002请参见图示。

此Wireshark 捕获输出的第7 行中执行的是哪一项TCP 操作？A会话创建B 数据段重传C 数据传输D 会话断开003数据段的TCP 报头中为什么包含端口号？A指示转发数据段时应使用的正确路由器接口B 标识接收或转发数据段时应使用的交换机端口C确定封装数据时应使用的第3 层协议让接收主机转发数据到适当的应用程序E让接收主机以正确的顺序组装数据包004OSI 模型哪一层负责规范信息从源设备到目的设备准确可靠地流动？A应用层 B 表示层 C 会话层传输层 E 网络层005请参见图示。

CCNA第一学期各章知识题及答案解析

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。

网络安全ccnas答案8

1.Which statement describes an important characteristic of a site-to-site VPN?It must be statically set up.It is ideally suited for use by mobile workers.It requires using a VPN client on the host PC.It is commonly implemented over dialup and cable modem networks.After the initial connection is established, it can dynamically change connection information.2.Which two statements accurately describe characteristics of IPsec? (Choose two.)IPsec works at the application layer and protects all application data.IPsec works at the transport layer and protects data at the network layer.IPsec works at the network layer and operates over all Layer 2 protocols.IPsec is a framework of proprietary standards that depend on Cisco specific algorithms.IPsec is a framework of standards developed by Cisco that relies on OSI algorithms.IPsec is a framework of open standards that relies on existing algorithms.3.When verifying IPsec configurations, which show command displays the encryption algorithm, hash algorithm, authentication method, and Diffie-Hellman group configured, as well as default settings?show crypto mapshow crypto ipsec sashow crypto isakmp policyshow crypto ipsec transform-set4.What are two benefits of an SSL VPN? (Choose two.)It supports all client/server applications.It supports the same level of cryptographic security as an IPsec VPN.It has the option of only requiring an SSL-enabled web browser.The thin client mode functions without requiring any downloads or software.It is compatible with DMVPNs, Cisco IOS Firewall, IPsec, IPS, Cisco Easy VPN, and NAT.5.How many bytes of overhead are added to each IP packet while it is transported through a GRE tunnel?81624326.When using ESP tunnel mode, which portion of the packet is not authenticated?ESP headerESP trailernew IP headeroriginal IP header7.Which UDP port must be permitted on any IP interface used to exchange IKE information between security gateways?4005006007008.Which action do IPsec peers take during the IKE Phase 2 exchange?exchange of DH keysnegotiation of IPsec policyverification of peer identitynegotiation of IKE policy sets9.What is the default IKE policy value for encryption?128-bit AES192-bit AES256-bit AES3DESDES10.A network administrator is planning to implement centralized management of Cisco VPN devices tosimplify VPN deployment for remote offices and teleworkers. Which Cisco IOS feature would provide thissolution?Cisco Easy VPNCisco VPN ClientCisco IOS SSL VPNDynamic Multipoint VPN11.A user launches Cisco VPN Client software to connect remotely to a VPN service. What does the user select before enteringusername and password?the SSL connection typethe IKE negotiation processthe desired preconfigured VPN server sitethe Cisco Encryption Technology to be applied12.With the Cisco Easy VPN feature, which process ensures that a static route is created on the Cisco EasyVPN Server for the internal IP address of each VPN client?Cisco Express ForwardingNetwork Access ControlOn-Demand RoutingReverse Path ForwardingReverse Route Injection13.Refer to the exhibit. Which two IPsec framework components are valid options when configuring an IPsec VPN on a Cisco ISR router? (Choose two.)Integrity options include MD5 and RSA.IPsec protocol options include GRE and AH.Confidentiality options include DES, 3DES, and AES.Authentication options include pre-shared key and SHA.Diffie-Hellman options include DH1, DH2, and DH5.14.Which two authentication methods can be configured when using the CCP Site-to-Site VPN wizard? (Choose two.)MD5SHApre-shared keysencrypted noncesdigital certificates15.Refer to the exhibit. A site-to-site VPN is required from R1 to R3. The administrator is using the CCPSite-to-Site VPN wizard on R1. Which IP address should the administrator enter in the highlighted field?10.1.1.110.1.1.210.2.2.110.2.2.2192.168.1.1192.168.3.116.Refer to the exhibit. Based on the CCP screen that is shown, which two conclusions can be drawn about the IKE policy that is being configured? (Choose two.)It will use digital certificates for authentication.It will use a predefined key for authentication.It will use a very strong encryption algorithm.It will be the default policy with the highest priority.It is being created using the CCP VPN Quick Setup Wizard.17.What is required for a host to use an SSL VPN to connect to a remote network device?VPN client software must be installed.A site-to-site VPN must be preconfigured.A web browser must be installed on the host.The host must be connected to a wired network.18.Refer to the exhibit. Based on the CCP settings that are shown, which Easy VPN Server component isbeing configured?group policytransform setIKE proposaluser authentication19.When configuring an IPsec VPN, what is used to define the traffic that is sent through the IPsec tunnel and protected by the process?crypto mapcrypto ACLISAKMP policyIPsec transform set20.Refer to the exhibit. A network administrator is troubleshooting a GRE VPN tunnel between R1 and R2. Assuming the R2 GRE configuration is correct and based on the running configuration of R1, what must the administrator do to fix the problem?Change the tunnel source interface to Fa0/0.Change the tunnel destination to 192.168.5.1.Change the tunnel IP address to 192.168.3.1.Change the tunnel destination to 209.165.200.225.Change the tunnel IP address to 209.165.201.1.。

思科第一学期第八章试题+答案

1为了让广告通过即时消息或电子邮件发送给尽可能多的用户，哪种互联网营销方法最为广泛使用？暴力攻击垃圾邮件间谍软件跟踪 cookie2安全策略在哪一部分规定了允许或拒绝的应用程序和用途？标识和身份验证远程访问可接受的使用事件处理3某用户上网时，屏幕上弹出一对话框声称其中奖。

该用户打开这个对话框后，计算机就被暗中安装了一个者现在可以访问该计算机并且检索到此用户的个人信息。

这是一种什么类型的攻击？蠕虫病毒特洛伊木马拒绝服务4Linksys 集成路由器的无线接入点部分连接到网络的哪一部分？DMZ外部内部除有线网络以外的其它网络5选择在社会工程攻击中使用的三种方法。

（选择三项。

）钓鱼语音网络钓鱼网络钓鱼滥发假托垃圾邮件6双防火墙网络设计最适合于哪种环境？大型企业环境包含 10 台或更少主机的家庭环境需要安全 VPN 访问的家庭环境遭到持续 DDoS 攻击的小型企业环境7蠕虫的主要特征是什么？不断在其它可执行程序中自我复制的一种恶意软件诱骗用户运行感染病毒的软件出现特定事件时才会被触发的一组计算机指令利用漏洞在网络中自我传播8哪个缩写词表示可同时供内部（即受信任的）设备以及外部（即不受信任的）设备访问的网络区域？SPIDMZISRISP9下列关于反病毒软件的陈述，哪一个是正确的？只有电子邮件程序需要保护。

只有硬盘可以保护。

只有在知道病毒后才能针对它创建反病毒更新。

只有直接连接 Internet 的计算机才需要安装反病毒软件。

10在网络假托过程中，行骗者通常采用什么方式联系目标？通过电子邮件通过电话亲身通过他人11下列哪个术语用于描述提供防火墙服务的专用硬件设备？基于服务器集成式个人基于设备12下列关于 Linksys 集成路由器中端口转发的陈述，哪一项是正确的？仅允许外网到特定内网端口的通信，其它通信均会被拒绝。

仅拒绝外网到特定内网端口的通信，其它通信均允许。

仅允许内网到特定外网端口的通信，其它通信均会被拒绝。