Computer Networking Quiz (or) Computer Networking MCQ (Multiple Choice Questions)

1 .

Which of the following is private IP address?

A)

12.0.0.1

B)

172.15.14.36

C)

168.172.19.39

D)

192.168.24.43

Correct Answer : Option (D) : 192.168.24.43

Explanation : Class A private address range is 10.0.0.0 through 10.255.255.255. Class B private address range is 172.16.0.0 through 172.31.255.255, and Class C private address range is 192.168.0.0 through 192.168.255.255.

2 .

Which class of IP address provides a maximum of only 254 host addresses per network ID?

A)

Class A

B)

Class B

C)

Class C

D)

Class D

Correct Answer : Option (C) : Class C

Explanation : A Class C network address has only 8 bits for defining hosts: 2² - 2 = 254.

3 .

Which statements are true regarding ICMP packets?

1. They acknowledge receipt of a TCP segment.

2. They guarantee datagram delivery.

3. They can provide hosts with information about network problems.

4. They are encapsulated within IP datagrams.

A)

3 and 4

B)

2 and 3

C)

2, 3 and 4

D)

None of the above

Correct Answer : Option (A) : 3 and 4

Explaination : Internet Control Message Protocol (ICMP) is used to send error messages through the network, but they do not work alone. Every segment or ICMP payload must be encapsulated within an IP datagram (or packet).

4 .

Which of the following are layers in the TCP/IP model?

1. Application

2. Session

3. Transport

4. Internet

5. Data Link

6. Physical

A)

1 and 2

B)

2, 3 and 5

C)

1, 3 and 4

D)

3, 4 and 5

Correct Answer : Option (C) : 1, 3 and 4

Explaination : This seems like a hard question at first because it doesn't make sense. The listed answers are from the OSI model and the question asked about the TCP/IP protocol stack (DoD model). However, let's just look for what is wrong. First, the Session layer is not in the TCP/IP model; neither are the Data Link and Physical layers. This leaves us with the Transport layer (Host-to-Host in the DoD model), Internet layer (Network layer in the OSI), and Application layer (Application/Process in the DoD).

5 .

Which layer 4 protocol is used for a Telnet connection?

A)

TCP

B)

UDP

C)

IP

D)

TCP/IP

Correct Answer : Option (A) : TCP

Explanation : Although Telnet does use TCP and IP (TCP/IP), the question specifically asks about layer 4, and IP works at layer 3. Telnet uses TCP at layer 4.

6 .

What protocol is used to find the hardware address of a local device?

A)

IP

B)

ARP

C)

ICMP

D)

RARP

Correct Answer : Option (B) : ARP

Explanation : Address Resolution Protocol (ARP) is used to find the hardware address from a known IP address.

7 .

Which of the following protocols uses both TCP and UDP?

A)

DNS

B)

FTP

C)

SMTP

D)

Telnet

Correct Answer : Option (A) : DNS

Explanation : DNS uses TCP for zone exchanges between servers and UDP when a client is trying to resolve a hostname to an IP address.

8 .

What is the address range of a Class B network address in binary?

A)

0xxxxxxx

B)

01xxxxxx

C)

110xxxxx

D)

10xxxxxx

Correct Answer : Option (D) : 10xxxxxx

Explanation : The range of a Class B network address is 128-191. This makes our binary range 10xxxxxx.

9 .

If you use either Telnet or FTP, which is the highest layer you are using to transmit data?

A)

Session

B)

Transport

C)

Application

D)

Presentation

Correct Answer : Option (C) : Application

Explanation : Both FTP and Telnet use TCP at the Transport layer; however, they both are Application layer protocols, so the Application layer is the best answer.

10 .

Which of the following commands sets the secret password to Cisco?

A)

enable secret cisco

B)

enable password Cisco

C)

enable secret password Cisco

D)

enable secret Cisco

Correct Answer : Option (D) : enable secret Cisco

Explanation : The enable secret password is case sensitive, so the second option is wrong. To set the enable secret <password>, use the enable secret <password> command from global configuration mode.