CCNA认证基础课程-课后作业.习题答案.doc

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 the correct answer from the list below. （3）1) 85 2) 90 3) BA 4) A1 5) B3 6) 1C 2. Convert the Hexadecimal number A2 into its Base 10 equivalent. Select the correct answer from the list below. （4）1) 156 2) 158 3) 160 4) 162 5) 164 6) 1663. Which binary number is a representation of the decimal number 248? （3）1) 11101000 2) 11110100 3) 11111000 4) 111110104. Which of the following will test the internal loopback of a node? （3）1) ping 2) ping 3) ping 4) ping 23 5) ping 555. What can be verified by successfully pinging the reserved loopback address on a 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-based computer to view the current IP configuration of the system? (Choose two.) （3，4）1) configip 2) ifconfig 3) ipconfig 4) winipcfg 5) Winipconfig7. Refer to the exhibit. What must be configured on Host B to allow it to communicate with the Host C? (Choose three.) （2，4，6）1) the MAC address of RTA router interface connected to Switch 1 2) a unique host IP address 3) the IP address of Switch 1 4) the default gateway address 5) the MAC address of Host C 6) the subnet mask for the LAN 8. What are important characteristics to consider when purchasing a network interface card? (Choose two.) （2，3）1) security used on the network 2) media used on the network 3) system bus used on the computer 4) software installed on the network 5) diagnostic tools installed on the network 第二章1. Select the necessary information that is required to compute the estimated time it would take to transfer data from one location to another. (Choose two.) （1，5）1) file size 2) data format 3) network in use 4) type of medium 5) bandwidth of the link 2. Using the data transfer calculation T=S/BW, how long would it take a 4MB file to be sent over a 1.5Mbps connection? （2）1) 52.2 seconds 2) 21.3 seconds 3) 6.4 seconds 4) 2 seconds 5) 0.075 seconds 6) 0.0375 seconds 3. What are features of the TCP/IP Transport layer? (Choose two.) （3，5）1) path determination 2) handles representation, encoding and dialog control 3) uses TCP and UDP protocols 4) packet switching 5) reliability, flow control and error correction4. Which of the following is the Layer 4 PDU? （4）1) bit 2) frame 3) packet 4) Segment5. What is important to remember about the data link layer of the OSI model when considering 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 data link functions. 6) It encodes the data link frame into a pattern of 1s and 0s (bits) for transmission on 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 at both ends. 2) Each host is connected to a hub or switch, either of which acts as a central point for 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 passed sequentially 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) DSL 2) Token Ring 3) Frame Relay 4) ISDN 5) Ethernet 9. Refer to the exhibit. Host A wants to send a message to host B. Place the following steps in 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, C 2) D, A, C, B 3) A, D, A, B 4) C, A, D, B 5) C, D, A, B 6) C, B, A, D 10. After an unsuccessful ping to the local router, the technician decides to investigate the router. 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) transport 2) network 3) data link 4) physical 11. Refer to the exhibit. What is the order of the TCP/IP Protocol Data Units as data is moved as indicated through the OSI model? （3）1) data, segments, frames, packets, bits 2) 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 neutral 2) neutral and positive 3) neutral and negative 4) positive and positive 5) positive and negative 6) negative and negative 2. Which of the following are considered the best media for use in data network communications? (Choose three.) （2，3，6）1) glass 2) fibers 3) copper 4) gold 5) plastic 6) silicon 7) Silver3. Which of the following wireless standards increased transmission capabilities to 11 Mbps? （2）1) 802.11a 2) 802.11b 3) 802.11c 4) 802.11d 4. What is attenuation? （3）1) opposition to the flow of current 2) measurement of electrical signals relative to time 3) degradation of a signal as it travels along the medium 4) amount or volume of traffic that is flowing on the medium 5. Which cable specifications are indicated by 10BASE-T? （3）1) 10 Mbps transmission speed, baseband signal, 500 meter cable length, coaxial cable 2) 10 Mbps transmission speed, broadband signal, 100 meter cable length, coaxial cable 3) 10 Mbps transmission speed, baseband signal, 100 meter cable length, twisted-pair cable 4) 10 Gbps transmission speed, broadband signal, 500 meter cable length, twisted-pair cable 6. For which Ethernet installations would fiber optic rather than Cat5 UTP be a better media choice? (Choose two.) （2，4）1) a 3 meter connection between two 10BASE-T hubs 2) an environment with many potential sources of EMI and RFI 3) a peer to peer connection between two NICs with RJ45 connectors 4) an installation between two buildings that are located 500 meters apart 5) a single building installation where installation costs are the major concern 7. Refer to the exhibit. Which type of UTP cable should be used to connect Host A to Switch1? （4）1) rollover 2) console 3) crossover 4) straight-through 8. Refer to the exhibit. Which type of Category 5 cable is used to make an Ethernet connection between Host A and Host B? （3）1) coax cable 2) rollover cable 3) crossover cable 4) straight-through cable 第四章1. During cable testing, which of the following are used to calculate the information carrying capacity of a data cable? (Choose two.) （2，5）1) bit speed 2) attenuation 3) wire map 4) saturation limit 5) analog bandwidth2. What type of wiring problem is depicted in this sample of a cable tester? （3）1) a fault 2) a short 3) an open 4) a split a good map3. In a new network installation, the network administrator has decided to use a medium that is not affected by electrical noise. Which cable type will best meet this standard? （5）1) coaxial 2) screened twisted pair 3) shielded twisted pair 4) unshielded twisted pair 5) fiber optic 4. How does network cable length affect attenuation? （3）1) Category 5 cable that is run in metal conduit has the highest attenuation in the shortest 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 which areas of a network? (Choose three.) （3，4，5）1) between workstation and backbone switch 2) between individual workstations 3) between backbone switches 4) between enterprise server and switch 5) on aggregate access links 2. What device must be used between an AUI port of a networking device and the media to which it is being connected? （3）1) a transducer 2) a transmitter 3) a transceiver 4) a transponder 5) a port replicator3. An ISDN Basic Rate Interface (BRI) is composed of how many signaling channels? （1）1) 1 2) 2 3) 3 4) 44. Which layer of the OSI model covers physical media? （1）1) Layer 1 2) Layer 2 3) Layer 3 4) Layer 4 5) Layer 5 6) Layer 65. What type of network cable is used between a terminal and a console port? （3）1) cross-over 2) straight-through 3) rollover 4) patch cable 6. What is the recommended maximum number of workstations configured on a peer-to-peer network? （3）1) 25 2) 15 3) 10 4) 5 5) 2 7. Which of the following increases the potential for a collision to occur? （4）1) the use of an active hub instead of an intelligent hub 2) the use of an intelligent hub instead of an active hub 3) a reduction in the number of devices attached to the hub 4) an increase in the number of devices attached to the hub 8. What is the maximum length of a media segment used for 100BASE-TX? （1）1) 100 meters 2) 185 meters 3) 400 meters 4) 500 meters9. Which cable diagram displays the end to end pinout for a crossover cable used with Cisco devices? （3）1) Cable A 2) Cable B 3) Cable C 4) 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 point 2) four Base10 digits separated by a decimal point 3) six hexadecimal digits 4) twelve hexadecimal digits 5) 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 devices have 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 PC 2) only router 3) PC and router 4) PC, hub, and router 5) 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 format 2) media 3) connectors 4) timing 5) multi-part encoding2. Which of the following does 1000BASE-T use to accomplish gigabit speeds on Cat 5e cable? （4）1) the use of four conductors in full-duplex mode 2) the use of two multiplexed pairs of wires, simultaneously 3) the use of three pairs of wires for data and the fourth for stabilization and forward error correction 4) 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 connection 2) mid-length voice 3) video conferencing 4) vertical wiring 5) horizontal wiring 6) diagonal wiring4. To make sure timing limitations are not violated when implementing a 10 Mbps Ethernet network involving hubs or repeaters, a technician should adhere to which rule? （4）1) the 4-5-3 rule 2) the 6-4-2 rule 3) the 3-4-5 rule 4) the 5-4-3 rule 5. What is the maximum distance that 10BASE-T will transmit data before signal attenuation affects the data delivery? （1）1) 100 meters 2) 185 meters 3) 300 meters 4) 500 meters6. When using Category 5 UTP cable, which RJ-45 pin pairs are used to exchange data between hosts on an Ethernet network? （2）1) 1 and 2; 4 and 5 2) 1 and 2; 3 and 63) 3 and 6; 7 and 8 4) 4 and 5; 7 and 8 第八章1. John has been hired as the network administrator of a local company and has decided to add more hubs to the companys existing network. Which of the following has been caused by Johns inexperience? （1）1) collision domain extended 2) an increased number of collision domains 3) increased network performance 4) increased bandwidth 5) extended bandwidth 2. 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 request 2) ARP request 3) ping 4) Telnet 5) proxy ARP 3. Which of the following is a term associated with replacing hubs with switches to increase the number of collision domains? （3）1) encapsulation 2) latency 3) segmentation 4) layered model 5) broadcast domain 6) Extended4. The accumulation of traffic from which of the following can cause a network condition called broadcast radiation? (Choose three.) （3，5，6）1) anonymous FTP servers 2) telnet sessions 3) video over IP applications 4) NAS services 5) ARP requests 6) RIP updates 5. Which of the following describes the use of Spanning Tree Protocol (STP)? （4）1) resolve routing loops 2) eliminate Split Horizon errors 3) limit collisions 4) resolve switching loops6. Which term describes the delay in time that occurs when a frame leaves its source device and reaches its destination? （4）1) collision 2) backoff 3) attenuation 4) latency 5) broadcast 7. Based on the graphic above, which of the following occurs as each host system comes 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) transceiver 2) router 3) switch4) hub 5) media 9. Which protocol is used to eliminate switching loops? （3）1) Transmission Control Protocol 2) Routing Information Protocol 3) Spanning Tree Protocol 4) Interior Gateway Routing Protocol 5) Internetworking Protocol 10. Refer to the exhibit. A network associate needs to establish an Ethernet connection 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) switch 2) hub 3) bridge 4) router 5) repeater 第九章1. Which term describes an ARP response by a router on behalf of a requesting host? （3）1) ARP 2) RARP 3) Proxy ARP 4) 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 with network access layer functions? (Choose two.) （2，4）1) configuring the e-mail client 2) installing NIC drivers 3) configuring IP network settings 4) connecting the network cable 5) using FTP to download application software updates4. Which part of an IP address identifies a specific device on a network? （4）1) first two octets 2) third and fourth octets 3) network portion 4) host portion 5) only the fourth octet 5. 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 subnet mask? (Choose three.) （2，3，5）1) 2) 0 3) 32 4) 5) 6) 7. Which application layer protocols use UDP at the transport layer? (Choose two.) （2，4）1) FTP 2) SNMP 3) Telnet 4) DHCP 5) SMTP第十章1. Which OSI layer encapsulates data into packets? （3）1) session 2) transport 3) network 4) data link 2. Which OSI layer defines the functions of a router? （3）1) physical 2) data link 3) network 4) transport 5) session3. Which of the following are Cisco proprietary routing protocols? (Choose two.) （2，6）1) RIPv2 2) IGRP 3) OSPF 4) BGP 5) RIPv1 6) EIGRP 4. A company with a Class B license needs to have a minimum of 1,000 subnets with each subnet capable of accommodating 50 hosts. Which mask below is the appropriate one? （4）1) 2) 3) 4) 92 5) 245. A small company has a class C network license and needs to create five usable subnets, each subnet capable of accommodating at least 20 hosts. Which of the following