CCNA第三学期中文答案期末考试
思科认证CCNA认证试题与答案中文版
答案：D 注释:这个题目不是太严谨,应该加上子网掩码. A:224. 0. 0. 5 是多播地址 B: 127. 0.0. 0 保留作为测试使用 C:网络地址 26、 设置主接口由 up 转 down 后延迟 30 秒切换到备份接口，主 接口 由 down 转 up 后 60 秒钟切换回主接口的配置为()
忍一句，息一怒，饶一着，退一步。——《增广贤文》
人之为学，不日进则日退，独学无友，则孤陋而难成；久处一方，则习染而不自觉。——《顾炎武》
答案：D 注释:255. 255. 255. 255 是全网广播,DHCP 客户端发送全网广播来 查 找 DHCP 服务器. 24、 下而有关 NAT 叙述正确的是() (A) NAT 是英文“地址转换”的缩写，又称地址翻译 (B) XAT 用来实现私有地址与公用网络地址之间的转换 (C) 当内部网络的主机访问外部网络的时候，一定不需要 NAT (D) 地址转换的提出为解决 IP 地址紧张的问题提供了一个有效途 径 答案:ABD 25、 以下属于正确的主机的 IP 地址的是()
(A) arp-a (B) traceroute (C) routeprint (D) displayiprouting-table
答案：D 23、 D0. 0. 0 (B) 10. 0. 0. 1 (0127. 0. 0. 1 (D)255. 255. 255. 255
192. 168. 1. 1
答案：D 注释:PC 的'默认网关要指向路由器的以太网口的 IP 地址. 28、 ISDNB 信道速率是()
(A) 16kbps (B) 64kbps
CCNA第三学期期末答案
假设没有使用 VLSM，添加 ip route 172.16.64.0 255.255.240.0 serial0/0 命令会对网络中正在工作的路由器造成什么影响？3目的地址处于 172.16.64.1 到 172.16.80.254 之间的所有数据包都会通过serial0/0 转发出去。
目的地址处于 172.16.64.1 到 172.16.255.254 之间的所有数据包都会通过serial0/0 转发出去。
目的地址处于 172.16.64.1 到 172.16.79.254 之间的所有数据包都会通过serial0/0 转发出去。
目的地址处于 172.16.0.1 到 172.16.64.254 之间的所有数据包都会通过serial0/0 转发出去。
2请参见图示。
管理员正在向网络中添加新路由器。
IP 地址 192.168.13.6/30 已被分配给 R2 上的相连串行接口。
管理员必须为新路由器的串行接口分配什么IP 地址？2192.168.13.4/30192.168.13.5/30192.168.13.7/30192.168.13.58/30192.168.13.61/27192.168.13.63/273OSPF 路由协议身份验证使用 MD5 验证时，下列有关密钥的说法中哪两项正确？（选择两项。
）24密钥以明文形式在路由器之间传递。
密钥用于帮助生成验证用的加密数字。
密钥以加密形式在路由器之间传递。
密钥永远不会在网络上传输。
数据包嗅探器可以捕获密钥。
4请参见图示。
路由表中将显示哪些路由？1R 10.10.4.0/24 [120/1] via 10.10.10.1, 00:00:12, FastEthernet0/1R 10.10.4.0/24 [120/1] via 10.10.20.1, 00:00:12, FastEthernet0/0R 10.10.4.0/24 [120/2] via 10.10.20.1, 00:00:12, FastEthernet0/0R 10.10.4.0/24 [120/3] via 10.10.30.1, 00:00:12, FastEthernet1/0R 10.10.4.0/24 [120/1] via 10.10.30.1, 00:00:12, FastEthernet1/05请参见图示。
CCNA认证试题(中文+答案)
CCNA认证试题一（附答案和解析）中文版(一)1、目前，我国应用最为广泛的LAN标准是基于（）的以太网标准.(A) IEEE 802.1(B) IEEE 802.2(C) IEEE 802.3(D) IEEE 802.5答案：C参考知识点：现有标准：IEEE 802.1 局域网协议高层IEEE 802.2 逻辑链路控制IEEE 802.3 以太网IEEE 802.4 令牌总线IEEE 802.5 令牌环IEEE 802.8 FDDIIEEE 802.11 无线局域网记住IEEE802.1-------IEEE802.5的定义以太网是一种计算机局域网组网技术。
IEEE制定的IEEE 802.3标准给出了以太网的技术标准。
它规定了包括物理层的连线、电信号和介质访问层协议的内容。
以太网是当前应用最普遍的局域网技术。
它很大程度上取代了其他局域网标准，如令牌环、FDDI和ARCNET。
以太网的标准拓扑结构为总线型拓扑，但目前的快速以太网（100BASE-T、1000BASE-T标准）为了最大程度的减少冲突，最大程度的提高网络速度和使用效率，使用交换机（Switch）来进行网络连接和组织，这样，以太网的拓扑结构就成了星型，但在逻辑上，以太网仍然使用总线型拓扑的C***A/CD介质访问控制方法。
电气电子工程师协会或IEEE（Institute of Electrical and Electronics Engineers）是一个国际性的电子技术及信息科学工程师的协会。
建会于1963年1月1日。
总部在美国纽约市。
在150多个国家中它拥有300多个地方分会。
目前会员数是36万。
专业上它有35个专业学会和两个联合会。
IEEE发表多种杂志，学报，书籍和每年组织300多次专业会议。
IEEE定义的标准在工业界有极大的影响。
下面列出：IEEE802．3以太网标准802.3--------- 10Base以太网标准802.3u-------- 100Base-T（快速以太网）802.3z-------- 1000Base-X（光纤吉比特以太网）802.3ab-------- 1000Base-T（双绞线吉比特以太网）2、对于这样一个地址,192.168.19.255/20,下列说法正确的是: （）(A) 这是一个广播地址(B) 这是一个网络地址(C) 这是一个私有地址(D) 地址在192.168.19.0网段上(E) 地址在192.168.16.0网段上(F) 这是一个公有地址答案：CE注：IP地址中关键是看她的主机位，将子网掩码划为二进制，1对应上面的地址是网络位，0对应的地址是主机位192.168.19.255/20划为二进制为：11000000.10101000.00010011.1111111111111111.11111111.11110000.00000000主机位变成全0表示这个IP的网络地址主机槐涑扇?表示这个IP的广播地址RFC1918文件规定了保留作为局域网使用的私有地址：10.0.0.0 - 10.255.255.255(10/8 prefix)172.16.0.0 - 172.31.255.255 (1 72.16/12 prefix)192.168.0.0 - 192.168.255.255 (192.168/16 prefix)3、Quidway系列路由器在执行数据包转发时，下列哪些项没有发生变化（假定没有使用地址转换技术）？（）(A) 源端口号(B) 目的端口号(C) 源网络地址(D) 目的网络地址(E) 源MAC地址(F) 目的MAC地址答案：ABCD参考知识点：路由功能就是指选择一条从源网络到目的网络的路径，并进行数据包的转发。
思科CCNA第三学期期末考试(完整版!!!)
参加考试 - ESwitching Final Exam - CCNA Exploration: LAN 交换和无线 (版本 4.0)1 以下哪项参数用于唯一标识一个无线网络，使其与其它网络区分开来？SSIDOFDMWEPDSSS2 分层网络模型具有哪三项优点？（选择三项。
）带宽争用现象减少物理布局范围减小网络的容错能力提高无需配线间无需第三层功能管理和故障排除工作简化3 在将 Catalyst 交换机迁移到其它 VTP管理域之前，应该进行哪三项任务？（选择正确的 VTP 模式和版本。
使用新管理域的名称配置交换机。
从新域中的 VTP 服务器上下载 VTP 数据库。
配置新域内的 VTP 服务器，使其识别该交换机的 BID 。
重置 VTP 计数器，使交换机可与新域内的其它交换机同步。
检验交换机的配置修订版号是否比新域内的其它交换机的低。
4下列哪两种说法正确地描述了生成树协议？（选择两项。
）它只在第2 层使用。
它在交换机上配置。
它消除了网络拓扑中的第 2 层环路。
它限制了端口上所允许的有效MAC 地址的数量。
它使VLAN 信息得以传播到网络中的其它交换机。
5下列哪种方法可建立用于配置Linksys WRT300N 无线接入点的管理连接？与接入点关联，然后与接入点建立超级终端会话。
以物理方式连接到接入点，然后重新启动计算机以启动配置软件。
在接入点所在的IP 子网内的计算机上的web 浏览器中输入接入点的默认IP 地址。
修改与接入点连接的计算机的TCP/IP 属性，使其与接入点处于同一个网络中，然后重新机以建立连接。
6请参见图示。
源地址并非0019.d2e4.d9f7 的帧进入接口Fa0/24 时会发生什么情况？Fa0/24 会变为error-disabled（错误-禁用）状态。
传入帧会被丢弃。
Fa0/24 端口LED 会关闭。
安全违规计数会增加。
7可采用哪两种方法删除交换机的MAC 地址表中的条目？（选择两项。
思科第三学期期末考试答案
请参见图示。
所有中继链路工作正常，而且允许所有VLAN使用所有中继链路。
计算机5 ARP请求。
哪台或哪些设备会收到此消息？仅计算机4* 计算机3和RTR-A计算机4和RTR-A计算机1、计算机2、计算机4和RTR-A计算机1、计算机2、计算机3、计算机4和RTR-A所有计算机和路由器F列关于在接入点上启用开放式身份验证的陈述，哪一项是正确的? *不需要身份验证使用64位加密算法需要使用身份验证服务器需要共同商定的密码VL^N Flane Status Ports1ctefauft active FaOl Fa0/2 FaO/3. Fa0/4 10accounting FaO/5. FaCVG Fa0.7 Fa0/820marking actr/e FaO/5, FaO'10, Fa(V11FaO/12. FaO/U FaO/14 research Faons, FaO/16 FaOH7FaO/16. FaO/19. Fa0/201QQ management adve FaO/21, FaQ/22. FaO'23Fa0/24, GiOJ1, G iO/21002W-default act/unsup1003loken-ring-1 efault act/unsup1004■fddinet-ctefaijlt act/unsup1005act/unsup请参见图示。
该交换机用于让图中所示部门的成员实现连接，但不存在路由。
连接到应该能够与accounting VLAN 中的用户通信。
下列哪项更改可实现所需通信？将该用户连接到GiO/1。
*将该用户连接到FaO/6。
将该用户添加到本征VLAN将该用户添加到默认VLAN分层网络模型具有哪三项优点？（选择三项。
）Opti on 1,36带宽争用现象减少」物理布局范围减小网络的容错能力提高无需配线间」无需第三层功能管理和故障排除工作简化FaO/22 IF列关于新交换机默认配置的说法中哪三项正确？（选择三项。
ccna_第三学期期末考试
1.VLAN 中继有何用途？通过减少广播流量提高网络性能。
选择在交换网络中传输数据的最佳路径。
通过一条链路传送多个VLAN 的流量。
避免交换网络中出现生成树环路。
请参见图示。
两台交换机都配置有默认的网桥优先级。
如果所有链路都在相同的带宽下运行，哪个端口将作为STP 根端口？S1 的Fa0/1 接口S1 的Fa0/2 接口S2 的Fa0/1 接口S2 的Fa0/2 接口请参见图示。
从图中显示的输出可以得到有关STP 的哪两项结论？（选择两项。
）交换机S1 所配置的STP 优先级值在该网络中最低。
交换机S1 被配置为VLAN1 的根桥。
Fa0/21 是交换机S1 的根端口。
Fa0/22 是冗余链路。
Fa0/24 被视为通往根桥的最佳路径。
下列哪种说法正确描述了生成树路径开销？根据环路中连接的交换机总数计算。
根据给定路径上所有交换机的使用率计算。
根据给定路径上交换机的网桥优先级计算。
根据给定路径上每个交换机端口的端口开销值（由端口速度决定）的总和计算。
使用单臂路由器模型配置VLAN 间路由有哪两项要求？（选择两项。
）每个子接口都应配置有自己的IP 地址、子网掩码和唯一的VLAN 分配。
路由器的物理接口必须连接到相邻交换机上的中继链路。
路由器的物理接口数量应该与VLAN 数量匹配。
应该将不同的静态VLAN 分配给路由器的不同接口。
路由器应该配置为VTP 服务器。
请参见图示。
下列哪两项正确描述了图中所示的路由器配置。
（选择两项。
）在路由器上配置路由协议之前，网络192.168.1.0 与网络192.168.3.0 之间无法成功路由。
路由器子接口上未正确配置VLAN。
该配置适用于单臂路由器网络设计。
路由器子接口上未正确配置中继。
应该为接口Fa0/1 分配IP 地址，否则无法进行路由请参见图示。
下列有关交换机S1 配置的说法中哪项正确？端口Fa0/1 和Fa0/3 使用的是Cisco 专有协议。
已使用switchport mode access命令配置交换机的Fa0/1 和Fa0/3 端口。
CCNA_第三学期__期末完整版考试
1CCNA 第三学期 期末While monitoring LAN traffic, a network technician notices an excessive number of broadcasts. Which two steps could be included in the processes that are needed to reduce the number of broadcasts onthe network? (Choose two.)Replace any existing hubs with switches.Add a Layer 3 device to route between networks.Subnet the existing IP network to create two networks.Increase the backbone speed by three times the current speed.Add additional switches and spread out the number of hosts evenly between them.2What advantage does cut-through switching provide?It enables QoSIt forwards frames quickly.It provides an analysis of frames.It allows reduction of traffic by using error checking to drop corrupt frames.3Refer to the exhibit. Which switch will be elected as the root bridge of the spanning tree topology?Cat-ACat-BCat-CCat-D4W hich stackable switch feature allows for interconnection of multiple switches and will provide a cost effective solution for networks that require high bandwidth and high availability?modular line cardsspecial backplane portdedicated gigabyte line portsaggregated FastEthernet ports5Refer to the exhibit. This switch is to be added to the production network. Which two facts about VLANs and VTP operation can be confirmed by this output? (Choose two.)The network administrator will be able to configure VLANs of local significance on this switch.VLANs can only be added to the VLAN database on this switch by a VTP advertisement.All VLANs that are configured on this switch will be sent to all other switches in the same VTP domain.This switch will drop all VTP advertisements that come from switches that are configured in the same VTP domain.Adding this switch to the network will cause no disruption in the VTP domain operations if the rest of the switches in the same VTP domain have a higher configuration revision number.6Refer to the exhibit. The hosts connected to switch SW1 are not able to communicate with the hosts in the same VLANs connected to switch SW2. What should be done to fix the problem?Configure VLANs with different VLAN IDs on switch SW2.Reconfigure the trunk port on switch SW2 with static trunk configuration.Introduce a Layer 3 device or a switch with Layer 3 capability in the topology.Apply IP addresses that are in the same subnet to the interfaces used to connect SW1 and SW2.7Refer to the exhibit. A new host needs to be connected to VLAN 3. Which IP address should beassigned to this new host?192.168.1.22 /28192.168.1.31 /28192.168.1.32 /28192.168.1.52 /28192.168.1.63 /288Refer to the exhibit. SW-T has been configured with a single trunking interface. Which VLANs will be allowed across the trunk?Only VLAN 1 will be allowed across the trunk.All configured VLANs will be allowed across the trunk.Only the native VLAN will be allowed across the trunk.Only the the management and native VLANs will be allowed across the trunk.Only VLANs that are configured on the VTP server in the domain will be allowed across the trunk.9Refer to the exhibit. How will switch S2 manage traffic coming from host PC1?S2 will drop the traffic, unless it is management traffic.S2 will tag the frame with VLAN ID 99 when it forwards it over the trunk link.S2 will leave the traffic untagged when it forwards it over a trunk link.S2 will tag the traffic with the highest VLAN ID value when it forwards it over the trunk link. 10Refer to the exhibit. Both switches are interconnected via a trunk link. Host A and host B are on the default VLAN but are not able to exchange traffic. What should be done to fix the problem?Allow all VLANs on the trunk link.Remove the native VLAN from the trunk.Include a router or switch with Layer 3 capabilities.Configure the same native VLAN on both ends of the trunk.11Refer to the exhibit. What does the term DYNAMIC indicate in the output that is shown?This entry can only be removed from the MAC address table by a network administrator.When forwarding a frame to the device with address 0060.5c5b.cd23, the switch does not have to perform a lookup to determine the final destination port.Only the device with MAC address 0060.5c5b.cd23 will be allowed to connect to port Fa0/18.The switch learned this MAC address from the source address in a frame received on Fa0/18.12W hy is MAC address filtering considered a poor choice in securing a WLAN?Available bandwidth is reduced.MAC addresses are easily spoofed.APs are more susceptible to DoS attacks.The payload encryption is easily broken.13How does a switch that is configured for 802.1Q trunking handle untagged frames that are receivedon a trunk port?The frames are dropped.The frames are assigned to the native VLAN.The frames are assigned to the default VLAN.The frames are assigned to the management VLAN.14Refer to the exhibit. Which three options correctly describe the router configuration that is shown?(Choose three.)An IEEE standard trunking protocol is in use.Interface Fa0/1 has been configured with subinterfaces.The shutdown command has been applied to interface Fa0/1.Interface Fa0/1.3 is mapped to the default management VLAN.The configuration is appropriate for a router-on-a-stick network design.An IP address should be applied to interface Fa0/1 for routing to occur.15RSTP is enabled in a switched network that is active and converged. Which switch port type assumesa discarding state on non-root switches?root portedge portalternate portdesignated port16What provides an authentication mechanism for 802.11-based wireless networks?DSSSOFDMSSIDWPA17W hat is the benefit of the auto-MDIX feature on a Cisco Catalyst switch?dynamically assigns a new management VLAN IDautonegotiates IP address information for initial management connectionsallows the use of straight-through patch cables regardless of connected device typesplaces a port immediately in the forwarding state to reduce the time for the spanning tree toreconverge18Refer to the exhibit. VTP pruning is enabled in the VTP domain that is shown. How will switch ST-1 handle Layer 2 broadcast traffic originating from host A on switch ST-C?It will be dropped.It will be forwarded out port Fa0/5 only.It will be forwarded out ports Fa0/5 and Fa0/10.It will be forwarded out ports Fa0/5, Fa0/10, and Fa0/15.19Refer to the exhibit. The network administrator wants to allow both SSH and Telnet connections to Switch1. However, the SSH connections fail. What is the most likely cause of this problem?The RSA key has been removed.SSH has been configured on the wrong line.The transport input command is applied incorrectly.The domain name has been configured in the wrong configuration mode.20Refer to the exhibit. The devices in the network are operational and configured as indicated in the exhibit. However, hosts B and D cannot ping each other. What is the most likely cause of this problem?The link between the switches is up but not trunked.The Fa0/11 interface of Switch1 is not configured as a trunk.Hosts B and D are configured with IP addresses from different subnets.VLAN 20 and VLAN 30 are not allowed on the trunk between the switches.21Refer to the exhibit. Hosts A and B, connected to hub HB1, attempt to transmit a frame at the same time but a collision occurs. Which hosts will receive the collision jamming signal?only hosts A and Bonly hosts A, B, and Conly hosts A, B, C, and Donly hosts A, B, C, and E22 A network administrator implements inter-VLAN routing by configuring subinterfaces on a router.What is one important fact that must be considered?The physical interface must have an IP address configured.The subinterface numbers must match the VLAN ID number.The no shutdown command must be issued on each subinterface.The IP address of each router subinterface must be used as the default gateway for hosts on the corresponding VLAN.23W hat is the purpose of VLAN trunking?It improves network performance by reducing broadcast traffic.It selects the best path to transmit data in a switched network.It carries the traffic of multiple VLANs through a single link.It avoids spanning tree loops in a switched network.24Which parameter is used to uniquely identify one wireless network from another?SSIDOFDMWEPDSSS25W hich layers should support QoS in a hierarchical network?only the distribution and core layersonly the access and distribution layersthe access, distribution, and core layers26Refer to the exhibit. What does "FORWARDING" mean in the command output shown?The switch is sending and receiving data frames.The switch is receiving BPDUs, but not sending data frames.The switch is participating in an election process by forwarding the BPDUs it receives.The switch is receiving BPDUs and populating the MAC address table, but not sending data.27Refer to the exhibit. A network administrator is configuring RT1 for inter-VLAN routing. The switch is configured correctly and is functional. Host1, Host2, and Host3 cannot communicate with each other.Based on the router configuration, what is causing the problem?Interface Fa0/0 is missing IP address configuration information.IP addresses on the subinterfaces are incorrectly matched to the VLANs.Each subinterface of Fa0/0 needs separate no shutdown commands.Routers do not support 892.1Q encapsulation on subinterfaces.28Which switch forwarding method should be used on a network that employs frame classification based on an assigned Quality of Service (QoS) value?cut-throughfast-forwardfragment-freestore-and-forward29Refer to the exhibit. A network administrator has segmented the network into two VLANs. The connected hosts can only access resources in their own VLAN. What is the most scalable and cost effective solution to allow inter-VLAN communication in this network?Replace S1 with a router that has one FastEthernet interface for each PC.Add a second switch and divide the PCs so that each VLAN is connected to its own switch.Configure a router with two subinterfaces on one of its FastEthernet ports and connect it to S1 using a trunk link.Connect a router to a port on S1 and assign the IP address of VLAN1 to the connecting router interface.30Refer to the exhibit. A network administrator issues the show interfaces fastEthernet 0/8switchport command to check the status of the port. What can be concluded from the output?Port Fa0/8 is configured as a trunk with 802.1q encapsulation.Port Fa0/8 is configured as a trunk in VLAN 1.Port Fa0/8 is configured in access mode and associated with VLAN 1.31What will be the effect of the command S1# copy system:running-configtftp://172.16.2.155/tokyo-config?The IOS will be copied to the TFTP server.The configuration file named tokyo-config will overwrite the startup configuration file on S1.The running configuration file on S1 will be saved via TFTP to a file named tokyo-config.The contents of NVRAM on S1 will become the startup configuration file on the tokyo switch.32W hich three statements are correct concerning the default configuration of a new switch? (Choose three.)It is configured in VTP server mode.STP is automatically enabled.The first VTY line is automatically configured to allow remote connections.VLAN1 is configured with a management IP address.All switch ports are assigned to VLAN1.The enable password is configured as cisco.33Refer to the exhibit. What would happen if the network administrator moved the network cable of Host A from interface Fa0/1 to Fa0/3 on switch SW1?Host A remains a member of VLAN 10, because the router is routing traffic between VLANs.Host A is no longer a member of VLAN 10, because port Fa0/3 has been manually assigned to VLAN 30.Host A remains a member of VLAN 10, because the switch provides dynamic VLAN assignment for the port.Host A maintains connectivity to all members of VLAN 10, because it is connected to the same physical network.Host A is no longer a member of VLAN 10, but because port Fa0/3 was unused, it is now amember of VLAN 1.34Refer to the exhibit. Switches S2 and S3 are properly connected using an ethernet cable. A network administrator has configured both switches with VTP, but S3 is unable to propagate VLANs to S2.What could be the reason for this?The VTP configuration revision is different on both switches.The VTP domains are different on both switches.VTP pruning is disabled.VTP v2 is disabled.35Refer to the exhibit. Users A and B are reporting intermittent connectivity problems. Pre-installation surveys showed strong signal strength from the AP locations to the client locations. Outside electricalIncrease the distance between the clients.Change the channel on AP-B to 6 or 11.Place AP-A and AP-B on the same wireless channel.36I n which mode is a VTP switch operating if it does not allow for the creation of local VLANs but it does accept VLAN updates from other switches in the same domain?clientrootservertransparent37Refer to the exhibit. The Layer 2 switching design that is shown has been implemented in a campus environment that is using Spanning Tree Protocol. All inter-switch links that are shown are trunks.Whenever an inter-switch link fails, the network takes nearly a minute to completely converge. How can the convergence time be reduced?Increase the capacity of the distribution and core trunk links to 10 Gb/s.Use Layer 3 switching on the core switch.Implement Rapid Spanning Tree Protocol.38Refer to the exhibit. Router R1 is properly configured for router on a stick inter-VLAN routing, but PC1 is unable to ping PC2. What needs to be done to resolve the problem?Rename VLAN1.Connect one more port of S1 to R1.Configure the Fa0/1 port of S1 as a trunk port.Move the Fa0/0 interface of R1 to another VLAN.39What is a result of improperly implementing a network with redundancy at Layer 2?an increase of unicast and multicast errors at Layer 3a decrease in the amount of broadcast trafficend device malfunction because of broadcast storms40W hy is it important that the network administrator consider the spanning-tree network diameter when choosing the root bridge?The network diameter limitation is 9.BPDUs may be discarded because of expiring timers.The cabling distance between the switches is 100 meters.The network diameter must be set to the number of meters of the cable between the root bridge and its farthest connected switch.41Refer to the exhibit. A network administrator needs to add IP phones to the network. To whichdevices should the IP phones connect?AS1 and AS2DS1 and DS2DS1, DS2, and CS1AS1, AS2, DS1, and DS242Which device or devices should have the Spanning Tree Protocol enabled to prevent host traffic from creating a broadcast storm?Core_S1Access_S2 and Access_S3Core_S1, Access_S2, and Access_S3Core_S1, Access_S2, Access_S3, and R143Refer to the exhibit. All edge ports are configured with the spanning-tree portfast command. Host1 is recently connected to port Fa0/1 on switch SW1 . Which statement is true about the status of port Fa0/1?The port will transition into blocking state.The port will transition immediately into forwarding state.The port will transition into blocking state and then immediately into forwarding state.The port will transition into blocking state and immediately transition through the listening and learning states.44A network administrator enables sticky learning on all access mode interfaces of a Catalyst switch, saves the configuration, then connects hosts to the switch. After the switch operates for several days, the administrator reboots the switch without saving the running configuration. What is the result?All previously learned MAC addresses are lost.The switch reverts to non-sticky dynamic learning.Connected hosts are no longer able to communicate with the switch.Previously learned sticky addresses are retained in the switch configuration.45The network administrator wants to configure a switch to pass VLAN update information to other switches in the domain but not update its own local VLAN database. Which two steps should the administrator perform to achieve this? (Choose two.)Reset the VTP counters.Configure VTP version 1 on the switch.Configure the VTP mode of the switch to transparent.Verify that the switch has a higher configuration revision number.Configure the switch with the same VTP domain name as other switches in the network.46Which statement regarding the service password-encryption command is true?The service password-encryption command is entered at the privileged EXEC mode prompt.The service password-encryption command encrypts only passwords for the console and VTY ports.The service password-encryption command encrypts all previously unencrypted passwords in the running configuration.To see the passwords encrypted by the service password-encryption command, enter the no service password-encryption command.47Refer to the exhibit. The network consists of four hubs and a switch. The hosts connected to each hub are assigned addresses in the respective VLAN as shown. PC1 on VLAN 1 becomes infected with a virus and initiates a continuous IP broadcast. Which hubs will receive the broadcasts?Hub AHubs A and BHubs A and CHubs A, B, C, and D48 A wireless LAN access point will convert traffic between which two frame encapsulation types?802.1 and 802.11802.3 and 802.11802.3 and 802.16802.5 and 802.1649I n the implementation of PVST+ in a specific VLAN where all switches have default spanning tree priorities, which spanning-tree command setting could be assigned to force one of the Catalyst switches to become and remain the root bridge?root primarypriority 8192priority 2048spanning-tree mode rapid pvst50Refer to the exhibit. The teacher host is connected to port Fa0/7 on switch STW. A student hasdecided to share access to the Internet by attaching a hub and laptop to STW as shown. What will be the result of the student making this connection?The Fa0/7 port of STW will be shutdown.The student will gain full access to the Internet.Both the teacher and student will be able to receive data but only the teacher will be able to send.The frames from the laptop will be dropped, but the teacher host will maintain connectivity with the network.51Refer to the exhibit. Switch SW2 was tested in a lab environment and then inserted into a production network without reloading its configuration. After the trunk link between SW1 and SW2 was brought up, all users lost connectivity to the network. What could be the source of the problem?All the VLANs were pruned from the trunk port between SW1 and SW2.SW1 and SW2 cannot be both set as VTP servers in the same VTP domain.VTP configuration revision number of SW2 was higher than the configuration revision number of SW1.The additional VLANs from SW2 created more VLANs than the VLAN database of SW1 could contain.。
CCNA考试题库中英文翻译版及答案
CCNA考试题库中英⽂翻译版及答案CCNA考试题库中英⽂翻译版及答案1[1]1、 What are two reasons that a network administrator would use access lists? (Choose two、)1、出于哪两种理由，⽹络管理员会使⽤访问列表?A、 to control vty access into a routerA、控制通过VTY访问路由器B、 to control broadcast traffic through a routerB、控制⼴播流量穿越路由器2、⼀个默认得帧中继WAN被分类为哪种物理⽹络类型?A、 point-to-pointA、点到点B、 broadcast multi-accessB、⼴播多路访问C、 nonbroadcast multi-accessC、⾮⼴播多路访问D、 nonbroadcast multipointD、⾮⼴播多点E、 broadcast point-to-multipointE、⼴播点到多点Answer: C3、 A single 802、11g access point has been configured and installed in the center of a squarA few wireless users are experiencing slow performance and drops while most users are oat peak efficiency、 What are three likely causes of this problem? (Choose three、)3、⼀个802、11接⼊点被部署在⼀个⽅形办公室得中央，当⼤多数⽤户在⼤流量传输数⼀些⽆线⽤户发现⽆线⽹络变得缓慢与出现丢包A、 mismatched TKIP encryptionB、 null SSIDC、 cordless phonesD、 mismatched SSIDE、 metalF、 antenna type or directionAnswer: CEF4、 Refer to the exhibit、 How many broadcast domains exist in the exhibited topology?根据下图，图中得拓扑中存在多少个⼴播域?A、 one A、1B、 two B、2C、 three C、3D、 four D、4E、 five E、5F、 six F、6Answer: C5、 Refer to the exhibit、 What two facts can be determined from the WLAN diagram? (Choose two、) 5、根据下图，WLAN diagram决定了哪两个事实A、 The area of overlap of the two cells represents a basic service set (BSS)、A、两个 cells得overlap得区域描述了⼀个basic service setB、 The network diagram represents an extended service set (ESS)、B、⽹络描述了⼀个extended service setC、 Access points in each cell must be configured to use channel 1、C、再每个CELL中得AP必须被配置成使⽤channel 1D、 The area of overlap must be less than 10% of the area to ensure connectivity、D、为了确保连通性,重叠区域必须⼩于10%E、 The two APs should be configured to operate on different channels、E、两个访问点应该被配置成⼯作在不同得频道Answer: BE6、 The command frame-relay map ip 10、121、16、8 102 broadcast was entered on the router、Which of the following statements is true concerning this command?6、路由器上输⼊命令frame-relay map ip 10、121、16、8 102 broadcast，以下选项正确得就是?A、 This command should be executed from the global configuration mode、A、该命令应该在全局配置模式下被执⾏B、 The IP address 10、121、16、8 is the local router port used to forward data、B、IP地址10、121、16、8就是本地路由器⽤来转发数据得接⼝C、 102 is the remote DLCI that will receive the information、C、102就是远端得DLCI它将接受信息。
CCNA认证试题(中文+答案)
CCNA认证试题一（附答案和解析）中文版(一）1、目前,我国应用最为广泛的LAN标准是基于(）的以太网标准.（A) IEEE 802。
1(B) IEEE 802。
2（C) IEEE 802.3（D）IEEE 802.5答案：C参考知识点：现有标准:IEEE 802.1 局域网协议高层IEEE 802.2 逻辑链路控制IEEE 802。
3 以太网IEEE 802.4 令牌总线IEEE 802。
5 令牌环IEEE 802.8 FDDIIEEE 802。
11 无线局域网记住IEEE802.1-——-—--IEEE802。
5的定义以太网是一种计算机局域网组网技术.IEEE制定的IEEE 802。
3标准给出了以太网的技术标准.它规定了包括物理层的连线、电信号和介质访问层协议的内容。
以太网是当前应用最普遍的局域网技术.它很大程度上取代了其他局域网标准,如令牌环、FDDI和ARCNET。
以太网的标准拓扑结构为总线型拓扑，但目前的快速以太网（100BASE—T、1000BASE-T标准）为了最大程度的减少冲突，最大程度的提高网络速度和使用效率，使用交换机（Switch）来进行网络连接和组织,这样，以太网的拓扑结构就成了星型，但在逻辑上，以太网仍然使用总线型拓扑的C**＊A/CD介质访问控制方法.电气电子工程师协会或IEEE（Institute of Electrical and Electronics Engineers）是一个国际性的电子技术与信息科学工程师的协会.建会于1963年1月1日。
总部在美国纽约市。
在150多个国家中它拥有300多个地方分会。
目前会员数是36万.专业上它有35个专业学会和两个联合会。
IEEE发表多种杂志,学报,书籍和每年组织300多次专业会议。
IEEE定义的标准在工业界有极大的影响.下面列出：IEEE802．3以太网标准802。
3--——---—— 10Base以太网标准802.3u-—------ 100Base-T（快速以太网）802.3z—-—————— 1000Base-X（光纤吉比特以太网）802.3ab———-——-— 1000Base—T（双绞线吉比特以太网）2、对于这样一个地址，192。
最新CCNA认证试题及答案「中文版」
最新CCNA认证试题及答案「中文版」1、对于这样一个地址,192.168.19.255/20,下列说法正确的是: ( )(A) 这是一个广播地址(B) 这是一个网络地址(C) 这是一个私有地址(D) 地址在192.168.19.0网段上(E) 地址在192.168.16.0网段上(F) 这是一个公有地址答案：CE注：IP地址中关键是看她的主机位，将子网掩码划为二进制，1对应上面的地址是网络位，0对应的地址是主机位192.168.19.255/20划为二进制为：11000000.10101000.00010011.1111111111111111.11111111.11110000.00000000主机位变成全0表示这个IP的网络地址主机槐涑扇?表示这个IP的广播地址RFC1918文件规定了保留作为局域网使用的私有地址：10.0.0.0 - 10.255.255.255 (10/8 prefix)172.16.0.0 - 172.31.255.255 (172.16/12 prefix)192.168.0.0 - 192.168.255.255 (192.168/16 prefix)2、目前，我国应用最为广泛的LAN标准是基于()的以太网标准.(A) IEEE 802.1(B) IEEE 802.2(C) IEEE 802.3(D) IEEE 802.5答案：C参考知识点：现有标准：IEEE 802.1 局域网协议高层IEEE 802.2 逻辑链路控制IEEE 802.3 以太网IEEE 802.4 令牌总线IEEE 802.5 令牌环IEEE 802.8 FDDIIEEE 802.11 无线局域网记住IEEE802.1-------IEEE802.5的定义以太网是一种计算机局域网组网技术。
IEEE制定的IEEE 802.3标准给出了以太网的技术标准。
它规定了包括物理层的连线、电信号和介质访问层协议的内容。
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请参见图示。
以下哪一项可以让交换机X 上VLAN 40 中的Y 上VLAN 40 中的主机通信？QoS路由(routing)中继VPN请参见图示。
每台交换机的MA 示。
如果为每台交换机配置了默认的优先级值，则哪台交换机会当选为生成树根桥？交换机A交换机B交换机C交换机D交换机E交换机 F请参见图示。
网络管理员输入图中所示的配置以SSH 和Telnet 连接访问交换机。
但Telnet 连接失败。
此问题最可能的原因是什么？SSH 版本号错误。
SSH 被配置在错误的线路上。
不能同时配置Telnet 和SSH。
transport input命令配置不正确。
请参见Switch4 的意义的说法中哪两项正确？（选择两项。
）此开销代表从Switch4 到根交换机的最低开销路径。
一台上游（更接近根交换机）交换机的端口16 正在向根交换机通告开销值23。
Switch4 将快速以太网链路的开销加到23 上来确定到根交换机的总开销。
Switch4 通过快速以太网链路连接到上游交换机，该上游交换机则通过千兆以太网链路连接到根交换机。
根交换机通告的开销值是23，该值比VLAN0001 生成树域内的其它任何交换机的值都低。
为什么网络管理员在选择根桥时必须考虑生成树网络直径？网络直径限制是9。
可以因为计时器到期而放弃BPDU。
交换机之间的布线距离是100 米。
必须将网络直径设置为根桥和与其相连的距离最远的交换机之间的电缆米数。
下列关于单臂路由器VLAN 间路由的说法中哪三项正确？（选择三项。
）需要使用路由器上的子接口需要在路由器和第 2 层交换机之间采用接入链路与采用多个物理接口相比，更经济且更具可扩展性需要在每个子接口上配置no shutdown命令如果许多VLAN 争夺单个路由器接口的带宽，则会影响性能与采用多个物理接口相比，排除VLAN 间路由配置故障简单得多请参见图示。
下列哪三项正确地描述了可能与此输出相关择三项）接口FastEthernet3/0/0 包含子接口。
正在使用非专有中继协议。
该配置适用于单臂路由器网络设计。
已经在接口FastEthernet3/0/0 上应用了shutdown命令。
接口FastEthernet3/0/0.3 被映射到默认的管理VLAN。
应该为FastEthernet3/0/0 分配IP 地址才能正确地路由数据。
请参见图示。
下列关于如图所示信息的确？当前仅将一个VLAN 配置为使用中继链路。
交换机为接口Fa0/1 和Gi0/1 协商中继链路。
接口Fa0/1 和Gi0/1 使用的是Cisco 专有协议。
允许接口Gi0/1 和Fa0/1 传输多个VLAN 的数据。
参见图示。
交换机SW2 在实验环境中经过测试，然后未重新加载配置就加入到生产环境中。
打开SW 间的中继链路后，所有用户均失去了网络连接。
问题的原因可能是什么？从SW1 和SW2 之间的中继端口剪除了所有VLAN。
不能将SW1 和SW2 都设置为同一VTP 域中的VTP 服务器。
SW2 的VTP 配置修订版号高于SW1 的配置修订版号。
SW2 产生了额外的VLAN，超过了SW1 的VLAN 数据库可容纳的数量。
示。
R1 被配置为进行传统的VLAN 间路由。
R1 可ping 通计算机3 但无法ping 通计算机1。
此故障的S1 的Fa0/11 端口处于错误的VLAN 中。
R1 上没有有效的路由协议。
计算机 1 的IP 地址在错误的逻辑网络中。
路由器的Fa0/0 接口上配置了错误的中继封装类型。
请参见图示。
将图中所列R1 和交换机S1 后，管理员输入show interface fa0/1 trunk命令并获得了图中所示的结果。
问题很可已建立中继链路，但未将任何VLAN 配置为使用该中继链路。
路由器上缺少建立中继链路所必要的动态中继协议语句。
未建立中继链路，因为该路由器不支持动态中继协议。
必须在路由器或交换机上或同时在这两台设备上配置dynamic desirable选项，动态中继协议才能建立中继链路请参见图示。
计算机A 发送了一则广播消到该广播消息？计算机B计算机B 和Router1计算机C 和Router1计算机B、计算机D、计算机 E 和Router1计算机B、计算机C、计算机D、计算机 E 和Router1计算机A、计算机B、计算机C、计算机D、计算机 E 和Router1如果将VTP 交换机配置为仅转发VTP 通告，则该交换机是处于什么工作模式？客户端根服务器透明请参见图示。
图中所示的交换机已启用VTP 修剪。
交换机ST-C 发往交换机ST-1 的VTP 通告中会剪除什么？VLAN 30VLAN 20 和VLAN 30VLAN 1、VLAN 20 和VLAN 30从VLAN 2 到VLAN 29 之间的VLAN 以及从VLAN 31 到VLAN 1000 之间的VLAN请参见图示。
该网络中的设备运行正常，其配置如图所示。
但是，主机B 和主机D 彼此无法ping 通。
此问题最可能的原因是什么？交换机之间的链路处于工作状态，但未配置为中继链路。
Switch1 的Fa0/11 接口未配置为中继接口。
主机 B 和主机 D 所配置的IP 地址属于不同子网。
不允许VLAN 20 和VLAN 30 使用交换机之间的中继链路。
下列哪种方法可建立用于配置Linksys WRT300N 无线接入点的管理连接？与接入点关联，然后与接入点建立超级终端会话。
以物理方式连接到接入点，然后重新启动计算机以启动配置软件。
在接入点所在的IP 子网内的计算机上的web 浏览器中输入接入点的默认IP 地址。
修改与接入点连接的计算机的TCP/IP 属性，使其与接入点处于同一个网络中，然后重新启动计算机以建立连接。
请参见图示。
图中所示的命令输出中的"FORWARDING" 表示什么意思？交换机正在发送并接收数据帧。
交换机正在接收BPDU，但未发送数据帧。
交换机正在通过转发收到的BPDU 参与选举过程。
交换机正在接收BPDU 并填充MAC 地址表，但并未发送数据。
请参见图示。
交换机SW1 所连接的主机无法与处于相同VLAN 中且连接到交换机SW2 的主机通信。
怎样才能纠正此问题？在交换机SW2 上采用另外的VLAN ID 配置VLAN。
使用静态中继配置重新配置交换机SW2 上的中继端口。
在拓扑中加入第 3 层设备或具备第 3 层功能的交换机。
将属于同一子网的IP 地址分配给用于连接SW1 和SW2 的接口。
请参见图示。
所有主机均处于侦听模式。
主机1 和数据。
网络中的主机会如何响应？（选择两项。
）在堵塞信号末尾会调用回退算法。
主机 1 和主机 4 会以全双工模式工作以避免冲突。
集线器会阻塞通向主机 4 的端口以避免冲突。
主机 1 和主机 4 会获分配更短的回退值，从而获得访问介质的优先权。
如果主机在回退时间结束后需要传送数据，主机会在传送前检查确定线路是否空闲。
请参见图示。
主机PC_B 同时发送流量，来自这两台发送站的帧发生了冲突。
最后收到冲突信号的是哪台设备？集线器HB1交换机SW1路由器R1交换机SW2路由器R2交换机SW4请参见图示。
新购置了交换机SW2络中。
应该向SW2 应用什么配置才能使其与交换机SW1 处于同一个VTP 域内，接收来自S息，并同步VLAN 信息？在SW2 上禁用VTP 修剪。
将SW2 配置为VTP 透明模式。
为SW2 配置VTP 域口令。
将SW2 配置为具有更高修订版号的VTP 服务器。
如果交换机的vty 线路配置有transport input ssh命令，则在该交换机上输入crypto key zeroize rsa命令况？会创建一个新的RSA 密钥对。
交换机默认为仅允许Telnet 连接。
交换机不再能作为SSH 客户端进行SSH 连接。
交换机仅在生成新的RSA 密钥对后允许远程连接。
络管理员需要设置Switch1，用于从HostA 进行远程访问。
管理员在Router1 上发出show i 命令，然后在Switch1 上发出show interfaces trunk命令以检验当前状态。
此外，管理员还将配置应用于Switch1。
但是，从HostA 尝试telnet 访问却失败了。
还需要对交换机发出哪些命Switch(config)# interface vlan 1Switch(config-if)# ip address 10.1.1.250 255.255.255.0 Switch(config-if)# no shutdownSwitch(config-if)# ip default-gateway 10.1.10.254Switch(config)# interface vlan 1Switch(config-if)# ip address 10.1.50.250 255.255.255.0 Switch(config-if)# no shutdownSwitch(config-if)# ip default-gateway 10.1.50.254Switch(config)# interface vlan 10Switch(config-if)# ip address 10.1.10.250 255.255.255.0 Switch(config-if)# no shutdownSwitch(config-if)# ip default-gateway 10.1.10.254Switch(config)# interface vlan 10Switch(config-if)# ip address 10.1.1.250 255.255.255.0Switch(config-if)# no shutdownSwitch(config-if)# ip default-gateway 10.1.10.254Switch(config)# interface vlan 50Switch(config-if)# ip address 10.1.10.250 255.255.255.0Switch(config-if)# no shutdownSwitch(config-if)# ip default-gateway 10.1.10.25424请参见图示。
网络划分为两个VLAN，并将Router1 配置为进行VLAN 间路由。
但是测试网络后发现，每个V能访问本地资源而不能访问另一个VLAN 中的资源。
此问题最可能的原因是什么？交换机端口Fa0/1 不是中继端口。
路由器的Fa0/0 接口可能已关闭。
Router1 上未配置路由协议。
路由器的一个子接口可能已关闭。
请参见图示。