思科认证考试

If the router R1 has a packet with a destination address 192.168.1.255, what describes the operation of the network（）。A、R1 will forward the packet out all interfaces.B、R1 will drop this packet because this it is not a valid IP address.C、As R1 forwards the

题目

If the router R1 has a packet with a destination address 192.168.1.255, what describes the operation of the network（）。

  • A、R1 will forward the packet out all interfaces.
  • B、R1 will drop this packet because this it is not a valid IP address.
  • C、As R1 forwards the frame containing this packet, Sw-A will add 192.168.1.255 to its MAC table.
  • D、R1 will encapsulate the packet in a frame with a destination MAC address of FF-FF-FF-FF-FF-FF
  • E、As R1 forwards the frame containing this packet, Sw-A will forward it to the device assigned the IP address of 192.168.1.255.
如果没有搜索结果，请直接 联系老师 获取答案。
如果没有搜索结果，请直接 联系老师 获取答案。
相似问题和答案

第1题：

When does the E－series router start monitoring DHCP traffic using the DHCP External function?()

A. When the discovery packet enters the router from the DHCP client.

B. Only when the offer packet enters the router from the DHCP server.

C. When the acknowledge packet enters the router from the DHCP server.

D. Only when the discovery packet leaves the router going to the DHCP server.


参考答案：D

第2题：

Router R1, a branch router, connects to the Internet using DSL. Some traffic flows through a GRE and IPsec tunnel, over the DSL connection, destined for an Enterprise network.Which of the following answers best describes the router‘s logic that tells the router, for a given packet, to apply GRE encapsulation to the packet?（）

A. When the packet received on the LAN interface is permitted by the ACL listed on the tunnel greacl command under the incoming interface

B. When routing the packet, matching a route whose outgoing interface is the GRE tunnel interface

C. When routing the packet, matching a route whose outgoing interface is the IPsec tunnel interface

D. When permitted by an ACL that was referenced in the associated crypto map


参考答案：B

第3题：

阅读下面的短文，回答问题 [When an IP packet arrives at a router, generally the router looks at the destination address of the packet, and forwards the packet to one of its network interfaces. The forwarding decision is usually done by looking up the destination address from another data structure called a forwarding table. The forwarding table is created by the router using the routing table and possible routing policies existing in the router. The router then creates a table where it lists which networks are accessible through which of the router’s network interfaces. An IP router looks at every IP packet individually and does the forwarding decision on a packet-by-packet basis. If something changes in the router’s routing table, a packet can take a different route from a preceding packet even if it has the same destination.] From the paragraph above，we can see that the router （ ） a forwarding table according to the routing table and possible routing policies existing in the router. When an IP packet arrives at a router, the （ ） part of packet is normally checked by the router. An IP router checks every IP Packet individually and makes the forwarding decision based on （ ）.

A．is generating B．generate C．is generated D．generates A．forwarding table B．network interfaces C．routing policies D．destination address A．the destination address and network interfaces B．forwarding table and network interfaces C．the destination address and forward table D．routing policies and routing table


正确答案：D,D,C

第4题：

If the router R1 has a packet with a destination address 192.168.1.255, what describes the operation of the network()。

A.R1 will forward the packet out all interfaces.

B.R1 will drop this packet because this it is not a valid IP address.

C.As R1 forwards the frame containing this packet, Sw-A will add 192.168.1.255 to its MAC table.

D.R1 will encapsulate the packet in a frame with a destination MAC address of FF-FF-FF-FF-FF-FF

E.As R1 forwards the frame containing this packet, Sw-A will forward it to the device assigned the IP address of 192.168.1.255.


参考答案：B

第5题：

Refer to the exhibit. EIGRP has been configured on routers R1 and R2. However, R1 does not show R2 as a neighbor and does not accept routing updates from R2.What could be the cause of the problem?()

A. The no auto - summary command has not been issued under the EIGRP process on both routers.

B. Interface E0 on router R1 has not been configured with a secondary IP address of 10.1.2.1/24.

C. EIGRP cannot exchange routing updates with a neighbor‘s router interface that is configured with tw o IP addresses.

D. EIGRP cannot form neighbor relationship and exchange routing updates with a secondary address.


参考答案：D

第6题：

During OSPF adjacency formation, in which state is a router in when an OSPF hello packet has been sent but bi－directional communication has not been achieved?()

A.A

B.B

C.C

D.D


参考答案：A

第7题：

Refer to the exhibit. Network 10.0.0.0／8 is being advertised to autonomous system 65550 via both external links. Which statement about the preferred path to the 10.0.0.0／8 network is true? ()

A. Router R2 will be preferred because it has the higher neighbor IP address.

B. Router R2 will be preferr ed because its neighbor has a lower autonomous system number.

C. Router R1 will be preferred because it has a lower local preference.

D. Router R2 will be preferred because it has a higher local preference.

E. Router R1 will be preferred because its nei ghbor has the higher autonomous system number.

F. Router R1 will be preferred because it has the lower neighbor IP address.


参考答案：D

第8题：

Router VE1 has just received a packet and needs to route it. What two actions must this router take in order to route incoming packets? (Choose two)

A. Inspect the routing table to select the best path to the destination network addresses.

B. Validate sources of routing information.

C. Inspect the ARP table to verify a legitimate source MAC address for each packet.

D. Identify the destination network address of each packet.

E. Verify the receipt of routed packets by the next hop router.

F. Identify the source network address of each packet.


正确答案：AD
A,D 解析：Explanation:
The router decides how to forward an incoming packet by finding the routes that "match" the destination address of the packet, and then forwarding it according to the most narrowly applicable one.

A packet matches a route in the following way: a packet has (among other things) a destination address in its header, a route contains either a network or a host address, a network mask (netmask), and instructions on how to forward a packet using the route.

The packet matches the route if its destination address is part of the address subspace defined by the network address or exactly matches the host address of the route. A route is more narrowly applicable than another if the address subspace defined by its network address contains fewer actual addresses than the other, which is indicated by the netmask. An entry with a host address, rather than a network address, is the narrowest kind.

第9题：

The following configuration line was added to router R1 Access－list 101 permit ip 10.25.30.00.0.0.255 any What is the effect of this access list configuration?()

A.ermit all packet smatching the first three octets of the source address to all destinations

B.permit all packet matching the last octet of the destination address and accept all source addresses

C.permit all packet matching the host bits in the source address to all destinations

D.permit all packet from the third subnet of the network address to all destinations


参考答案：A

第10题：

Anytime a host or a router has an IP datagram to send to another host or router, it has the（　）address of the receiver. This address is obtained from the DNS if the sender is the host or it is found in a routing table if the sender is a router. But the IP data gram must be（　） in a frame to be able to pass through the physical network. This means that the sender needs the （　）address of the receiver. The host or the router sends an ARP query packet. The packet includes the physical and IP addresses of the sender and the IP address of the receiver. Because the sender does not know the physical address of the receiver, the query is（　） over the network.Every host or router on the network receives and processes the ARP query packet, but only the intended recipient recognizes its IP address and sends back an ARP response packet.The response packet contains the recipient's IP and physical addresses. The packet is（请作答此空） directly to the inquirer by using the physical address received in the query packet.

A. multicast
B. unicast
C. broadcast
D. multiple unicast

答案：B
解析：
任何时候主机或路由器要发送 IP 数据报发送给另一主机或路由器时，都需要知道接收方的逻辑地址。发送主机从 DNS 获得该地址，发送路由器则在路由表中找到该地址。但 IP 数据报必须封装在帧中才能通过物理网络。这意味着发送者需要知道接收者的物理地址。主机或路由器需发送 ARP 查询报文，该报文分组包含发送者的物理地址和 IP 地址及接收者的 IP 地址。这是因为送者不知道接收者的物理地址，所以需在全网广播报文。网络上的每个主机或路由器都能接收并处理该 ARP 查询报文，但只有预期的接收者识别其 IP 地址并响应该 ARP 报文。响应报文包含接收者的 IP 地址和物理地址。包含了接收者物理地址的响应报文分组通过单播的方式直接发送给发送者。

更多相关问题
相关内容