2023年6月24日发(作者：)

思科《计算机⽹络》期末考试答案A卷A卷—正确率98.21．Which subnet would include the address 192.168.1.96 as a usable host address?192.168.1.32/27192.168.1.32/28192.168.1.64/29192.168.1.64/ is a characteristic of the LLC sublayer?It provides the logical addressing required that identifies the places information in the frame allowing multiple Layer 3 protocols to use the same network interface and provides delimitation of data according to the physical signaling requirements of the defines software processes that provide services to the physical are the three primary functions provided by Layer 2 data encapsulation? (Choose three.)data link layer addressingerror correction through a collision detection methodplacement and removal of frames from the mediadetection of errors through CRC calculationsdelimiting groups of bits into framesconversion of bits into data signalssession control using port name is assigned to the transport layer PDU? many valid host addresses are available on an IPv4 subnet that is configured with a /26 mask? applied to a router, which command would help mitigate brute-force password attacks against the router?login block-for 60 attempts 5 within 60exec-timeout 30banner motd

Maxfailedlogins=5service password-encryption7 . Which range of link-local addresses can be assigned to an IPv6-enabled interface?FE80::/10FDEE::/7FF00::/8FEC0::/ are two ways that TCP uses the sequence numbers in a segment? (Choose two.)to determine if the packet changed during transitto identify missing segments at the destinationto specify the order in which the segments travel from source to destinationto limit the number of segments that can be sent out of an interface at one timeto reassemble the segments at the remote location9 . A network team is comparing physical WAN topologies for connecting remote sites to a headquarters building. Whichtopology provides high availability and connects some, but not all, remote sites?partial meshpoint-to-pointhub and spokemesh10 . What are two services provided by the OSI network layer? (Choose two.)placement of frames on the mediarouting packets toward the destinationencapsulating PDUs from the transport layerperforming error detectioncollision detection11 . Match the description with the associated IOS mode. (Not all options are used.)user EXEC modelimited number of basic monitoring commandsthe first entrance into the CLI of an IOS deviceprivileged EXEC modeaccessed by entering the enable commandidentified by a prompt ending with the # characterglobal configuration modechanges made affect the operation of the device as a wholeaccessed by entering the configure terminal command12 . What is a benefit of using cloud computing in networking?Home networking uses existing electrical wiring to connect devices to the network wherever there is an electrical outlet,saving the cost of installing data logy is integrated into every-day appliances allowing them to interconnect with other devices, making them more‘smart’ or users have the freedom to use personal tools to access information and communicate across a business k capabilities are extended without requiring investment in new infrastructure, personnel, or software.13 . Refer to the exhibit. A network administrator is configuring access control to switch SW1. If the administrator uses aconsole connection to connect to the switch, which password is needed to access user EXEC mode?letmeinsecretinlineconinlinevtyin14 . Which frame forwarding method receives the entire frame and performs a CRC check to detect errors beforeforwarding the frame?fragment-free switchingfast-forward switchingstore-and-forward switchingcut-through switching15 . A wireless host needs to request an IP address. What protocol would be used to process the request?SNMPHTTPICMPFTPDHCP16 . What is an advantage to using a protocol that is defined by an open standard?It encourages competition and promotes open standard protocol is not controlled or regulated by standards protocol can only be run on equipment from a specific vendor.A company can monopolize the market.17 . A network administrator is troubleshooting connectivity issues on a server. Using a tester, the administrator noticesthat the signals generated by the server NIC are distorted and not usable. In which layer of the OSI model is the errorcategorized?network layerdata link layerpresentation layerphysical layer18 . What protocol is responsible for controlling the size of segments and the rate at which segments are exchangedbetween a web client and a web server?HTTPEthernetIPTCP19 . Which statement is true about variable-length subnet masking?Subnets may only be subnetted one additional subnet is the same size of each subnet may be different, depending on are returned, rather than borrowed, to create additional subnets.20 . What is a characteristic of UTP cabling?immunity to electrical hazardswoven copper braid or metallic foilcancellationcladding21．A site administrator has been told that a particular network at the site must accommodate 126 hosts. Which subnetmask would be used that contains the required number of host bits?255.255.255.240255.255.255.224255.255.255.0255.255.255.12822 . On which switch interface would an administrator configure an IP address so that the switch can be managed remotely?FastEthernet0/1VLAN 1vty 0console 023．What is a characteristic of a fault tolerant network?a network that recovers quickly when a failure occurs and depends on redundancy to limit the impact of a failurea network that can expand quickly to support new users and applications without impacting the performance of the servicedelivered to existing usersa network that protects confidential information from unauthorized accessa network that supports a mechanism for managing congestion and ensuring reliable delivery of content to all users24．What method is used to manage contention-based access on a wireless network?CSMA/CDCSMA/CAtoken passingpriority ordering25．What are two benefits of using a layered network model? (Choose two.)It speeds up packet prevents designers from creating their own assists in protocol prevents technology in one layer from affecting other ensures a device at one layer can function at the next higher layer.26．What is an example of a top-level domain?27 . Which connection provides a secure CLI session with encryption to a Cisco switch?an SSH connectionan AUX connectiona Telnet connectiona console connection28．What is the dotted decimal representation of the IPv4 address 11001011.00000000.01110001.11010011?209.165.201.223203.0.113.211198.51.100.201192.0.2.19929 . Refer to the exhibit. What will be the result of entering this configuration the next time a network administratorconnects a console cable to the router and no additional commands have been entered?The administrator will be required to enter Cisco123 .The administrator will be required to enter Cisco234 .The administrator will be presented with the R1> administrator will be required to enter Cisco789.30．What addresses are mapped by ARP?destination IPv4 address to the source MAC addressdestination MAC address to the source IPv4 addressdestination MAC address to a destination IPv4 addressdestination IPv4 address to the destination host name31 . A network technician is attempting to configure an interface by entering the following command: SanJose(config)# ipaddress 192.168.2.1 255.255.255.0 . The command is rejected by the device. What is the reason for this?The command syntax is command is being entered from the wrong mode of interface is shutdown and must be enabled before the switch will accept the IP subnet mask information is incorrect.32．An administrator uses the Ctrl-Shift-6 key combination on a switch after issuing the ping command. What is thepurpose of using these keystrokes?to allow the user to complete the commandto restart the ping processto interrupt the ping processto exit to a different configuration mode33 . A network technician suspects that a particular network connection between two Cisco switches is having a duplexmismatch. Which command would the technician use to see the Layer 1 and Layer 2 details of a switch port?show interfacesshow ip interface briefshow mac-address-tableshow running-config34 . What will a host on an Ethernet network do if it receives a frame with a destination MAC address that does not matchits own MAC address?It will remove the frame from the will discard the will forward the frame to the next will strip off the data-link frame to check the destination IP address.35．What is the function of the shell in an OS?It interacts with the device interfaces between the users and the provides the intrusion protection services for the provides dedicated firewall services.36．What purpose does NAT64 serve in IPv6?It converts IPv6 packets into IPv4 converts the 48-bit MAC address into a 64-bit host address that can be used for automatic host converts regular IPv6 addresses into 64-bit addresses that can be used on the translates private IPv6 addresses into public IPv6 enables companies to use IPv6 unique local addresses in the network.37 Refer to the exhibit. If host A sends an IP packet to host B, what will the destination address be in the frame when itleaves host A?CC:CC:CC:CC:CC:CC172.168.10.65DD:DD:DD:DD:DD:DDBB:BB:BB:BB:BB:BBAA:AA:AA:AA:AA:AA172.168.10.9938．What is a key characteristic of the peer-to-peer networking model?network printing using a print serverresource sharing without a dedicated serverwireless networkingsocial networking without the Internet39 . Three bank employees are using the corporate network. The first employee uses a web browser to view a company webpage in order to read some announcements. The second employee accesses the corporate database to perform somefinancial transactions. The third employee participates in an important live audio conference with other corporate managersin branch offices. If QoS is implemented on this network, what will be the priorities from highest to lowest of the differentdata types?financial transactions, web page, audio conferenceaudio conference, web page, financial transactionsaudio conference, financial transactions, web pagefinancial transactions, audio conference, web page40．Where are Cisco IOS debug output messages sent by default?console linevty linesSyslog servermemory buffers41 . What are two characteristics of fiber-optic cable? (Choose two.)It is not affected by EMI or is more expensive than UTP cabling combines the technique of cancellation, shielding, and twisting to protect pair of cables is wrapped in metallic typically contains 4 pairs of fiber-optic wires.42 . A PC obtains its IP address from a DHCP server. If the PC is taken off the network for repair, what happens to the IPaddress?The address is permanent and nothing address is held by the server to be reissued when the PC is address is returned to the pool for reuse when the lease address lease is automatically renewed until the PC is returned.43．Which scenario describes a function provided by the transport layer?A corporate worker is accessing a web server located on a corporate network. The transport layer formats the screen so theweb page appears properly no matter what device is being used to view the web site.A student is playing a short web-based movie with sound. The movie and sound are encoded within the transport layerheader.A student has two web browser windows open in order to access two web sites. The transport layer ensures the correct webpage is delivered to the correct browser window.A student is using a classroom VoIP phone to call home. The unique identifier burned into the phone is a transport layeraddress used to contact another network device on the same network.44 . A network administrator is measuring the transfer of bits across the company backbone for a mission critical financialapplication. The administrator notices that the network throughput appears lower than the bandwidth expected. Which threefactors could influence the differences in throughput? (Choose three.)the amount of traffic that is currently crossing the networkthe sophistication of the encapsulation method applied to the datathe type of traffic that is crossing the networkthe latency that is created by the number of network devices that the data is crossingthe bandwidth of the WAN connection to the Internetthe reliability of the gigabit Ethernet infrastructure of the backbone45 . What are two functions of NVRAM? (Choose two.)to contain the running configuration fileto store the routing tableto store the ARP tableto retain contents when power is removedto store the startup configuration file46．What are the three ranges of IP addresses that are reserved for internal private use? (Choose three.)127.16.0.0/12172.16.0.0/1210.0.0.0/8192.31.7.0/24192.168.0.0/1664.100.0.0/1447 . Which two OSI model layers have the same functionality as two layers of the TCP/IP model? (Choose two.)physicaltransportsessionnetworkdata link48 Refer to the exhibit. Match the packets with their destination IP address to the exiting interfaces on the router. (Not alltargets are used.)FastEthernet0/0· packets with destination of 172.17.6.15FastEthernet0/1· packets with destination of 172.17.14.8FastEthernet1/0· packets with destination of 172.17.12.10FastEthernet1/1· packets with destination of 172.17.10.5Serial0/0/0· packets with destination of 172.17.8.20The packet is dropped.49 . What is the most compressed representation of the IPv6 address 2001:0000:0000