CCNA 2 v5 Chapter 4: Check Your Understanding Questions Answers

CCNA 2 Routing and Switching Essentials v5 Chapter 4: Routing Concepts – Check Your Understanding Questions Answers

1. Which two statements correctly describe the components of a router? (Choose two.)

RAM permanently stores the configuration file used during the boot sequence.
ROM contains diagnostics executed on hardware modules.
NVRAM stores a backup copy of the IOS used during the boot sequence.
Flash memory does not lose its contents during a reboot.
ROM contains the most current and most complete version of the IOS.
Flash contains boot system commands to identify the location of the IOS.

Explanation: Read-Only Memory (ROM): Provides permanent storage for bootup instructions, basic diagnostic software, and a limited IOS in case the router cannot load the full featured IOS. Flash: Provides permanent storage for the IOS and other system related files. The IOS is copied from flash into RAM during the bootup process. Flash is nonvolatile and does not lose its contents when power is turned off.

2. Which three statements describe features of Cisco devices that perform routing? (Choose three.)

The IP address of a LAN interface on a Layer 3 device provides the default gateway for hosts connected to that LAN.
A routing protocol must be enabled in order for a Layer 3 device to build a routing table.
Routing tables are volatile. When power is removed from a Layer 3 device, the routing table ceases to exist.
A routing table is automatically created for directly connected, active LAN and WAN interfaces.
A directly connected Layer 3 interface must be manually added to the routing table in order for routing to be enabled on that interface.

Explanation: A routing table entry for a directly connected IPv4 or IPv6 network is automatically added to the routing table when the corresponding interface is up. The interface vlan and ip address commands are used on a switch to assign an IP address to the device. As seen in the chapter content and lab activities, addressing and activating LAN and WAN interfaces automatically trigger the building of a routing table in a Layer 3 device.

3. What address and prefix length is used when configuring an IPv6 default static route?

::/0
::1/128
0.0.0.0/0
FF02::1/8

Explanation: The IPv6 address and prefix for a default static route is ::/0. This represents all zeros in the address and a prefix length of zero.

4. What is the purpose of a routing protocol?

It is used to build and maintain ARP tables.
It provides a method for segmenting and reassembling data packets.
It allows an administrator to devise an addressing scheme for the network.
It allows a router to share information about known networks with other routers.
It provides a procedure for encoding and decoding data into bits for packet forwarding.

Explanation: Routing protocols allow routers to exchange routing information about known networks.

5. Which tasks can be accomplished by using the command history feature? (Choose two.)

View a list of commands entered in a previous session.
Recall up to 15 command lines by default.
Set the command history buffer size.
Recall previously entered commands.
Save command lines in a log file for future reference.

Explanation: The command history feature is useful because it temporarily stores the list of executed commands to be recalled. By default, command history is enabled and the system captures the last 10 command lines in its history buffer.

6. During the process of encapsulation, how does the PC determine if the packet is destined for a host on a remote network?

By checking the ARP cache for the destination host MAC address
By querying the DNS server for the information of the destination host
By sending a broadcast to the local LAN segment to see if there is any response
By performing the AND operation on the destination IP address and its own subnet mask

Explanation: When a PC needs to encapsulate a frame to send a data packet, it first performs an AND operation with its own IP and subnet mask, which yields the network address. Then it performs another AND operation using the destination IP and the same subnet mask. By comparing the two AND operations results, the PC knows if the destination is on the local LAN or on a remote network.

7. When a router learns that multiple paths are available to a destination network from the same routing protocol, which factor is considered by a router to choose the best path to forward a packet?

The lowest metric
The order of paths on the routing table
The fastest bandwidth of exiting interfaces
The reliability value of the neighboring routers

Explanation: When a router learns that multiple paths are available to a destination network from the same routing protocol, the route with the lowest metric is put into the routing table to forward packets toward that network.

8. Which two statements describe characteristics of load balancing? (Choose two.)

Load balancing occurs when a router sends the same packet to different destination networks.
Load balancing occurs when the same number of packets is sent over static and dynamic routes.
Load balancing allows a router to forward packets over multiple paths to the same destination network.
Unequal cost load balancing is supported by EIGRP.
If multiple paths with different metrics to a destination exist, the router cannot support load balancing.

Explanation: When a router has two or more paths to a destination with equal cost metrics, then the router forwards the packets using both paths equally. Only EIGRP supports unequal cost load balancing.

9. What is a Gateway of Last Resort?

The IP address of another router
The IP address of the Internet provider
A term to describe a default gateway on a host device
Where dropped packets are sent

Explanation: Even though a gateway of last resort could be an IP address of an ISP router, this does not have to be the case. A gateway of last resort, as seen in a Cisco routing table, is simply the IP address that is used to route packets addressed to networks not explicitly listed in the routing table. A Windows- based computer uses the term default gateway, not gateway of last resort.

10. Refer to the exhibit. What is the purpose of the router port that is shown?

CCNA 2 v5 Chapter 4: Check Your Understanding Questions Answers 1

To back up the IOS
To configure the router
To run an IOS from an alternative location
To connect to a port on a switch

Explanation: The exhibited port is a USB port that is found on some Cisco router models. This USB port provides console access to the router, which allows access to the CLI for configuration purposes. The pale blue background behind the icon is also the standard color that is used on Cisco devices to indicate a console connection.

11. What code is used in the routing table to identify routes learned through EIGRP?

Explanation: Each route in a routing table has a code that identifies how the route was learned by the router. The code letter D is used to identify routes learned through EIGRP.

12. Which two statements describe static routes? (Choose two.)

They are created in interface configuration mode.
They require manual reconfiguration to accommodate network changes.
They automatically become the default gateway of the router.
They are identified in the routing table with the prefix S.
They are automatically updated whenever an interface is reconfigured or shut down.

Explanation: Static routes are manually configured. They define an explicit path between two networking devices. Unlike a dynamic routing protocol, static routes are not automatically updated and must be manually reconfigured if the network topology changes. A static route is identified in the routing table with the code S.

13. The output of the show ip route command contains the following entry:

S 10.2.0.0 [1/0] via 172.16.2.2.

What value is indicated by the 1 in the [1/0] portion of the output?

Metric
Number of hops
Administrative distance
Interface ID through which the network can be reached

Explanation: In the routing table entry, S 10.2.0.0 [1/0] via 172.16.2.2, the numbers inside the bracket indicate the administrative distance and metric, respectively.