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Routing Concepts

  • Sample Chapter is provided courtesy of Cisco Press.
  • Date: Jan 1, 2018.

Chapter Description

This sample chapter from Routing and Switching Essentials v6 Companion Guide, answer the question, “What does a router do with a packet received from one network and destined for another network?” Details of the routing table will be examined, including connected, static, and dynamic routes.

Check Your Understanding Questions

Complete all the review questions listed here to test your understanding of the topics and concepts in this chapter. The appendix, “Answers to the ‘Check Your Understanding’ Questions,” lists the answers.

  1. Which of the following correctly explains a network characteristic?

    1. Availability indicates how easily the network can accommodate more users and data transmission requirements.

    2. Reliability is often measured as a probability of failure or as the mean time between failures (MTBF).

    3. Scalability is the likelihood that the network is available for use when it is required.

    4. Usability is how effectively end users can use the network.

  2. What are two functions of a router? (Choose two.)

    1. It connects multiple IP networks.

    2. It controls the flow of data via the use of Layer 2 addresses.

    3. It determines the best path to send packets.

    4. It increases the size of the broadcast domain.

    5. It manages the VLAN database.

  3. Which two statements correctly describe the concepts of administrative distance and metric? (Choose two.)

    1. Administrative distance refers to the trustworthiness of a particular route.

    2. A router first installs routes with higher administrative distances.

    3. Routes with the smallest metric to a destination indicate the best path.

    4. The metric is always determined based on hop count.

    5. The metric varies depending which Layer 3 protocol is being routed, such as IP.

    6. The value of the administrative distance cannot be altered by the network administrator.

  4. For packets to be sent to a remote destination, what three pieces of information must be configured on a host? (Choose three.)

    1. Default gateway

    2. DHCP server address

    3. DNS server address

    4. Hostname

    5. IP address

    6. Subnet mask

  5. What is a characteristic of an IPv4 loopback interface on a Cisco IOS router?

    1. It is a logical interface internal to the router.

    2. It is assigned to a physical port and can be connected to other devices.

    3. Only one loopback interface can be enabled on a router.

    4. The no shutdown command is required to place this interface in an “up” state.

  6. What two pieces of information are displayed in the output of the show ip interface brief command? (Choose two.)

    1. Interface descriptions

    2. IP addresses

    3. Layer 1 statuses

    4. MAC addresses

    5. Next-hop addresses

    6. Speed and duplex settings

  7. A packet moves from a host on one network to a device on a remote network within the same company. In most cases, which two items remain unchanged during the transfer of the packet from source to destination? (Choose two.)

    1. Destination MAC address

    2. Destination IP address

    3. Layer 2 header

    4. Source ARP table

    5. Source MAC address

    6. Source IP address

  8. Which two items are used by a host device when performing an ANDing operation to determine whether a destination address is on the same local network? (Choose two.)

    1. Destination MAC address

    2. Destination IP address

    3. Network number

    4. Source MAC address

    5. Subnet mask

  9. Refer to Example 1-28. What will the router do with a packet that has a destination IP address of

    1. Drop the packet.

    2. Send the packet out the GigabitEthernet0/0 interface.

    3. Send the packet out the GigabitEthernet0/1 interface.

    4. Send the packet out the Serial0/0/0 interface.

  10. Which two parameters does EIGRP use as metrics to select the best path to reach a network? (Choose two.)

    1. Bandwidth

    2. Confidentiality

    3. Delay

    4. Hop count

    5. Jitter

    6. Resiliency

  11. What route would have the lowest administrative distance?

    1. A directly connected network

    2. A route received through the EIGRP routing protocol

    3. A route received through the OSPF routing protocol

    4. A static route

  12. Consider the following routing table entry for R1:

    D [90/2170112] via, 00:00:05, Serial0/0/0

    What is the significance of the Serial0/0/0?

    1. It is the interface on R1 used to send data that is destined for

    2. It is the interface on the final destination router that is directly connected to the network.

    3. It is the interface on the next-hop router when the destination IP address is on the network.

    4. It is the R1 interface through which the EIGRP update was learned.

  13. Refer to Example 1-19. A network administrator issues the show ipv6 route command on R1. What two conclusions can be drawn from the routing table? (Choose two.)

    1. Interface G0/1 is configured with IPv6 address 2001:DB8:ACAD:2::12.

    2. Network FF00::/8 was learned from a static route.

    3. Packets destined for the network 2001:DB8:ACAD:1::/64 will be forwarded through G0/1.

    4. Packets destined for the network 2001:DB8:ACAD:2::/64 will be forwarded through G0/1.

    5. R1 does not have any remote network routes.

  14. A network administrator configures interface G0/0 on R1 with the ip address command. However, when the administrator issues the show ip route command, the routing table does not show the directly connected network. What is the possible cause of the problem?

    1. Interface G0/0 has not been activated.

    2. No packets with a destination network of have been sent to R1.

    3. The configuration needs to be saved first.

    4. The subnet mask is incorrect for the IPv4 address.

  15. A network administrator configures a router using the command ip route What is the purpose of this command?

    1. To add a dynamic route for the destination network to the routing table

    2. To forward all packets to the device with IP address

    3. To forward packets destined for the network to the device with IP address

    4. To provide a route to forward packets for which there is no route in the routing table

  16. What are two common types of static routes in routing tables? (Choose two.)

    1. A built-in static route by IOS

    2. A default static route

    3. A static route converted from a route that is learned through a dynamic routing protocol

    4. A static route that is dynamically created between two neighboring routers

    5. A static route to a specific network

  17. What command will enable a router to begin sending messages that allow it to configure a link-local address without using an IPv6 DHCP server?

    1. A static route

    2. The ip routing command

    3. The ipv6 route ::/0 command

    4. The ipv6 unicast-routing command

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