Module 3 Quiz

Question 1

Which of the following is a component you wouldn’t expect to find associated with a Cisco Integrated Services Router?

Answer 1

a.Random access memory

b.Read-only memory

c.Content addressable memory

d.Central processing unit

e.Flash memory

The Cisco ISR has many components in common with a desktop PC. The following are some of the components you would expect to find in an ISR:

CPU (Central Processing Unit): Similar to a PC, it executes operating system instructions.
RAM (Random Access Memory): This is a type of memory that loses its contents when the power is shut down. Similar to the memory in a PC, it stores temporary (running) configuration settings and the routing table.
ROM (Read-only Memory): As with a PC, it stores the device’s POST instructions.
NVRAM (Non-volatile RAM): This is a form of memory that retains information when power is lost. This memory stores the saved configuration file of the device.
Flash memory: This serves a similar purpose as the hard drive in a PC, by providing long-term storage of several versions of the operating system.
Interfaces: These are the interfaces for connecting to the network, such as Fast Ethernet, Serial and Management interfaces. PCs have equivalent interfaces, but routers tend to have more network interfaces than would be found on a PC.
A Cisco switch stores its MAC table using content addressable memory.

Question 2

Cisco divides campuses into three layers. The core layer, the distribution layer and the access layer. All user devices connect to switches in the access layer. In smaller networks, the access layer is not necessary, and its functions may be folded into the distribution layer. In such cases, the network is said to follow a collapsed core design.

Answer 2

Select one:
True
False

Cisco divides campuses into three layers. The core layer, the distribution layer and the access layer. All user devices connect to switches in the access layer. The access layer switches sit on the edge of the LAN and send traffic to and from end user devices. The access layer switches also connect to switches in the distribution layer and since the distribution layer switches connect to several access switches, it provides a way to communicate between end devices in separate parts of the LAN. For redundancy, there may be several links between the distribution and access switches. Large networks would have extra high-speed switches which connect the distribution layer switches that have been distributed across the geographic area of the campus. In such cases, the network is said to have a 3-tier design. In smaller networks, the core layer is not necessary, and its functions may be folded into the distribution layer. In such cases, the network is said to follow a collapsed core design.

Question 3

The Parent route contains the classful network address and prefix applicable to all of its child routes. Child routes are related to a specific parent routes and always contain an exit interface, indicating from where the traffic should be sent in order to reach the destination. A(n) Ultimate route is an entry in the routing table that may be used to route traffic.

Answer 3

Parent, Child, Ultimate, Dynamic

The routing table consists of two levels of entries, namely

Parent routes: The parent route contains the classful network address and prefix applicable to all of its child routes. The child routes of the parent may have different subnet masks, but all share the same classful network address. The entry in the routing table will indicate how many child routes the parent contains, as well as how many different subnet masks it contains. A parent route does not contain a destination and cannot be used to route traffic. These routes are also called level 1 routes.
Child routes: Child routes are related to a specific parent routes and always contain an exit interface, indicating from where the traffic should be sent in order to reach the destination. These routes may be used to route traffic. These routes are also called level 2 routes.
An ultimate route is an entry in the routing table that may be used to route traffic. To qualify as an ultimate route, the route entry requires an exit interface.

Question 4

State whether the following is true or false:

RIP uses cost as its metric.

Answer 4

True

False

Question 5

The prefix length in an IPv6 address defines how many bits of the address are associated with the address prefix.

Answer 5

TRUE
False

IPv6 does not use a subnet mask like IPv4. It does however make use of a prefix mask, which follows a similar format to that of IPv4, namely a ‘/’ followed by a decimal number. Instead of defining the ‘network’ portion of the IPv6 address, the prefix length in an IPv6 address defines how many bits of the address are associated with the address prefix, which is in essence similar to the ‘network’ portion of an IPv4 address. The valid range for a prefix is 0 to 128.

Question 6

The default route is like a catch-all route which is used whenever no other route in the routing table matches the destination.

Answer 6

The [default] route is like a catch-all route which is used whenever no other route in the routing table matches the destination.

Question 7

Which of the following internetworking devices places all of its attached devices in the same collision domain?

Answer 7

a.Repeater

b.Hub

c.Switch

Question 8

When a switch port is set to operate in Half‑duplex mode the port may transmit and receive, but it may not do both at the same time. In Full‑duplex mode the port may transmit and receive at the same time.

Answer 8

When a switch port is set to operate in [Half‑duplex] mode the port may transmit and receive, but it may not do both at the same time. In [Full‑duplex] mode the port may transmit and receive at the same time.

Question 9

The following image contains 3 separate topologies. How many collision domains are there across all 3?

Answer 9

All devices connected to a hub are in the same collision domain. Every interface on a switch is in a separate collision domain.

Each colour link in the following image represents a different collision domain - 9 in total

Question 10

Which of the following is not a way in which a router learns an IP route?

Answer 10

a.The router can dynamically learn routes from a routing protocol. These routes are called dynamic routes.

b.Interfaces in an up/up state are added to the routing table as directly connected routes.

c.Routes may be manually added to the routing table with the ip route command. This is called a static route.

d.Entries are built up using the CAM table.

A router learns these IP routes in three ways:

Interfaces in an up/up state are added to the routing table as directly connected routes.
Routes may be manually added to the routing table with the ip route command. This is called a static route.
The router can dynamically learn routes from a routing protocol. These routes are called dynamic routes.

Question 11

MAC is a type of memory used in high-speed searching applications.

Answer 11

True
FALSE

Question 12

NDP uses two types of messages called Neighbor Solicitation (NS) and Neighbor Advertisement (NA) messages. The ________ message is used to send the response, containing the requested MAC address. The ________ is used in a similar fashion to the IPv4 ARP request, i.e. it is used to request that a host with a specific IPv6 address responds with its MAC address.

Answer 12

NDP uses two types of messages called Neighbor Solicitation (NS) and Neighbor Advertisement (NA) messages. The [NA] message is used to send the response, containing the requested MAC address. The [NS] is used in a similar fashion to the IPv4 ARP request, i.e. it is used to request that a host with a specific IPv6 address responds with its MAC address.

NDP uses two types of messages called Neighbor Solicitation (NS) and Neighbor Advertisement (NA) messages. The NS is used in a similar fashion to the IPv4 ARP request, i.e. it is used to request that a host with a specific IPv6 address responds with its MAC address. The NA message is used to send the response, containing the requested MAC address. The difference between ARP requests and NS messages are that the ARP requests are sent as a broadcast (which requires all devices on the network to process it), whereas the NS messages are sent using a multicast address. The multicast is usually sent to the solicited node multicast address. The solicited node multicast address is automatically created by taking the last 24 bits of the specific IP address and appending them to the prefix FF02::1:FF00:0/104. Only hosts whose IP addresses match these last 24 bits will respond to the multicast. The following table illustrates an example of a solicited node multicast address.

Question 13

What class is the following IP address?

211.110.122.157

Answer 13

a.A

b.B

c.C

d.D

e.E

f.
None, the address is invalid.

There are strict but simple rules for determining into which class an IP address falls. In essence, the value of the first octet defines the class of the IP address. The following table outlines the various classes of IPv4 addresses.

Class
First octet value
Purpose
Number of networks
Number of hosts per network
Network IDs
Class A
1 - 126
Unicast
126
16 777 214
1.0.0.0 – 126.0.0.0
Class B
128 - 191
Unicast
16 384
65 534
128.0.0.0 – 191.255.0.0
Class C
192 - 223
Unicast
2 097 152
254
192.0.0.0 – 223.255.255.0
Class D
224 – 239
Multicast
-
-
-
Class E
240 – 255
Experimental
-
-
-

The highest value allowed in any IPv4 address octet is 255. If an address contains values lower than 0 or higher than 255, the address is not valid.

Question 14

What class is the following IP address?

60.1.1.10

Answer 14

a.A

b.B

c.C

d.D

e.E

f.
None, the address is invalid

Question 15

The routing table is built from various information sources. Match the description with the information source.

Answer 15

These are networks that have been added to the routing table by the network administrator.
Static routes

These are networks that are physically connected (by cable) to the router.
Directly connected networks

These are routes that are added to the routing table by receiving information from the routing protocols running on other routers.
Dynamic routes

The routing table is built from various information sources, namely:

Directly connected networks: These are networks that are physically connected (by cable) to the router.
Static routes: These are networks that have been added to the routing table by the network administrator.
Dynamic routes: These are routes that are added to the routing table by receiving information from the routing protocols running on other routers. This process requires no administrator intervention, except for the initial routing protocol setup.

Question 16

Cisco devices support three different types of frame forwarding. Match the forwarding type with its definition.

Answer 16

Attempts to reduce the number of errored frames by ensuring that the switch processes the first 64 bytes of a frame before forwarding it.
Fragment-free

The switch starts sending the frame out on the destination port as soon as the destination address can be read.
Cut-through

Requires that the switch (or bridge) receives the entire frame before it is able to forward it.
Store-and-forward

Store-and-forwardswitching requires that the switch (or bridge) receives the entire frame before it is able to forward it. This is the slowest form of switching, since every frame must be processed and stored in its entirety before it may be forwarded.

When cut-through processing is used, the switch starts sending the frame out on the destination port as soon as it is able to do so, i.e. as soon as the destination address can be read.

Fragment-free processing works on a similar process to cut-through processing, but it attempts to reduce the number of errored frames by ensuring that the switch processes the first 64 bytes of a frame before forwarding it.

Question 17

Which of the following commands is used to display the routing table on a Windows device?

Answer 17

a.show route

b.route print

c.show ip route

d.show ipv4 route

e.ip route print

The IPv4 routing table on a Cisco device may be displayed by issuing the following command:

show ip route

PCs also have routing tables, but the focus of this section is on the routing table on a router. If you are interested in seeing the routing table of a Windows device, the device’s routing table may be requested from the command prompt by issuing the following command:

route print

Question 18

What class is the following IP address?

200.11.12.13

Answer 18

a.A

b.B

c.C

d.D

e.E

f.
None, the address is invalid.

Question 19

What class is the following IP address?

191.11.12.13

Answer 19

a.A

b.B

c.C

d.D

e.E

f.
None, the address is invalid.

Question 20

Address Resolution Protocol (ARP) is a layer 2 protocol used to determine a destination ____ address for a specific ____ address.

Answer 20

Address Resolution Protocol (ARP) is a layer 2 protocol used to determine a destination [MAC] address for a specific [IPv4] address.

Address Resolution Protocol (ARP) is a layer 2 protocol used to determine a destination MAC address for a specific IPv4 address. Host devices, such as PCs, and networking devices, such as routers, maintain a list of IPv4 address to MAC address mappings in a structure known as the ARP table, also referred to as the ARP cache.

Question 21

The administrative (admin) distance is a measure of the trustworthiness of a route. Match the admin distance to the routing information source.

Answer 21

The following are a few well-known admin distances:

0: Directly connected
1: Static route
20: External BGP
90: Internal EIGRP
110: OSPF
120: RIP

Question 22

When a router powers on, it follows these four steps:

Answer 22

Step Description
1. [A Power On Self Test (POST) process is run.]
2. [A bootstrap program is executed.]
3. [An IOS image is loaded into RAM.]
4. [The router attempts to load a start‑up configuration file.]

When a router first powers on, it follows these four steps:

A Power On Self Test (POST) process is run. The POST process in routers and PCs is used to discover hardware components and verify that they work correctly.
A bootstrap program is copied from ROM into Random Access Memory (RAM) and executed.
An IOS image (or the ROMMON OS) is selected by the bootstrap program and loaded into RAM. The bootstrap program then hands control to the router hardware to continue the startup process.
If an IOS image was loaded (not the ROMMON OS) the router attempts to load a start-up configuration file from non-volatile RAM (NVRAM). The startup configuration file contains the settings by which the device will be configured once booting has completed. This file is similar to a settings file in Windows, Mac OS and other operating systems. The startup configuration file is loaded into RAM and is then referred to as the running configuration file. If the device is unable to find a startup configuration file (either locally or on a remote server) it will provide the user with a wizard or command-line interface (CLI) in order to perform initial device configuration.

Question 23

The routing table is built from various information sources. Match the description with the information source.

Answer 23

These are networks that have been added to the routing table by the network administrator.
Answer 1
Static routes

These are networks that are physically connected (by cable) to the router.
Answer 2
Directly connected networks

These are routes that are added to the routing table by receiving information from the routing protocols running on other routers.
Answer 3
Dynamic routes

The routing table is built from various information sources, namely:

Directly connected networks: These are networks that are physically connected (by cable) to the router.
Static routes: These are networks that have been added to the routing table by the network administrator.
Dynamic routes: These are routes that are added to the routing table by receiving information from the routing protocols running on other routers. This process requires no administrator intervention, except for the initial routing protocol setup.