Networking Refresher Section Quiz

Question 1

Which layer of the OSI model do IP addresses use?

Answer 1

Layer 3.

Question 2

Which technology prevents us from running out of IPv4 addresses?

Answer 2

NAT (Network Address Translation).

Question 3

Which layer of the OSI model do Media Access Control (MAC) addresses use?

Answer 3

Layer 2.

Question 4

What are MAC addresses used for?

Answer 4

Communication through switches.

Question 5

The first three hexadecimal digits of a mac address tell you…

Answer 5

The vendor that produced the unit.

Question 6

What are the steps for the Three-Way handshake?

Answer 6

SYN > SYN ACK > ACK

Question 7

As the CIDR number increases (e.g. from /24 to /25), the number of hosts in a subnet decreases or increases?

Answer 7

Decreases.

Question 8

What is the subnet mask of /16?

Answer 8

255.255.0.0

Question 9

True or false: In 10.10.0.0/16, the addresses 10.11.15.1 and 10.10.15.1 are valid.

Answer 9

False. The address 10.11.15.1 is invalid. The netmask is 255.255.0.0 so the first two octets should not change.

Question 10

What is a Routing Table?

Answer 10

It’s a data table that stores particular network destinations.

Question 11

What does a 0.0.0.0 value mean in the “Destination” column?

Answer 11

It has the same value as a ‘*’, so it’ll match any ip address.

Question 12

What does a 0.0.0.0 value mean in the “Gateway” column?

Answer 12

It means send direct, there is no need to route the packet to another network because the destination is on the same one.

Question 13

In a routing table, what values does the “Genmask” column hold?

Answer 13

The subnet mask of the destination, 0.0.0.0 for the default one.