Ghazni University
Computer Science Faculty
IT Department
Answer key
Multiple Choice Questions(1 Mark):
1: Which protocol is used for secure communication over the internet:
A: HTTP B: FTP C: HTTPS D:SMTP
2:What is the purpose of a router in a network?
a:To connect multiple devices within a local area network
b:To connect different networks together and route data between them
c:To provide wireless connectivity to devices d: To manage the flow of data
3: ICMP stands for :
A: Inter computing message protocol B: Intra control message protocol C: Inter control
message protocol D: A and C
4:which layer of the OSI model is responsible for routing and addressing?
a: Network Layer b: Data Link c: Transport Layer d:Application Layer
5: IP address is used in which layer
A: Presentation Layer B: Application C: Network D: Datalink
6: Transmission media is divided into parts
A :2 B:3 C:4 D:5
7:Which of the following option is not belongs to unguided media
A: Radio wave B: Microwave C: Coaxial D: Infrared
8: Repeater is Used in which layer
A: layer one B: Layer two C: Layer three D: None
9: IP address is a …….. Bit address
A: 33 B: 31 C: 32 D: 34
10: In Classful addressing the address space is divided into …… classes
A: 4 B: 5 C: 7 D:2
11: This IP address(190.223.1.108) is belongs to Class
A: A B: C C: B D: E
12: This IP address(01000001 00001011 00001011 11101111) is belongs to Class
A: A B: C C: B D: E
13: Class D IP addresses are used for
A: Routing B: Multicasting C: Broadcasting D: Both A and B
14:How many usable IP address classes do we have
A: 2 B: 3 C: 4 D:5
15:which layer is responsible for Translation and Encryption of data?
a: Network Layer b: Data Link c: Presentation Layer d:Application Layer
Note: Please write the correct option in bellow table.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Descriptive Questions(6 mark):
1. NIC (Network Interface Card)
A Network Interface Card (NIC) is a hardware component that allows a computer or
device to connect to a network, such as a LAN (Local Area Network) or the internet. It
can be built into the motherboard or added as an external card.
2. Usage
Network connectivity, data transmission, unique identification, supports communication
protocols, enable internet access.
3. TCP (Transmission Control Protocol) and UDP (User Datagram Protocol):
o TCP:
Reliable, connection-oriented protocol.
Ensures data integrity, sequencing, and error recovery.
Used for web browsing, email (SMTP), file transfer (FTP), etc.
o UDP:
Connectionless protocol.
Faster but less reliable.
Used for real-time applications (VoIP, video streaming), DNS, and gaming.
4. Subnetting, Subnet, and Subnet Mask:
o Subnetting: Dividing a larger IP address space into smaller independent address spaces
(subnets).
o Subnet: A smaller network within a larger network, created through subnetting.
o Subnet Mask: Distinguishes network and host portions within an IP address.
o
5. Address Ranges Reserved for Private Usage:
o IPv4 Private Addresses:
10.0.0.0–10.255.255.255
172.16.0.0–172.31.255.255
192.168.0.0–192.168.255.255
o .
6. Bridge in Computer Networks:
o A bridge connects two or more LAN segments and control the traffic of network.
o Usage:
Integrating LANs: Bridges join LANs with similar protocols.
Increasing Network Capacity: Multiples the network capacity of a single LAN.
7. Infrared Waves and Their Uses:
o Infrared (IR) waves have longer wavelengths than visible light.
o Usages:
Remote Controls: IR signals control TVs, air conditioners, and other devices.
Thermography: Detecting heat patterns (e.g., in medical imaging or building
inspections).
Communication: IR data transmission (e.g., IrDA for short-range wireless
communication).
Night Vision: IR cameras capture images in low-light conditions.
Security Systems: Motion sensors and alarms use IR detection8.
Computational Question(9)
7:
It is class C ip address , netid=192.168.1.0 Range(192.168.1.0-192.168.1.255)
8:
Subnet Network ID First Host Last Host Broadcast ID
Subnet 1 160.20.0.0 160.20.0.1 160.20.63.254 160.20.63.255
Subnet 2 160.20.64.0 160.20.64.1 160.20.127.254 160.20.127.255
Subnet 3 160.20.128.0 160.20.128.1 160.20.191.254 160.20.191.255
