PSEB-XII SERIES Computer-applications
Computer Networks
4 previous year questions.
Volume: 4 Ques
Yield: Medium
High-Yield Trend
4
2026 Chapter Questions 4 MCQs
01
PYQ 2026
medium
computer-applications ID: pseb-xii
Explain the different types of network topologies (Bus, Star, Ring, Mesh).
Official Solution
Correct Option: (1)
Concept: A network topology refers to the physical or logical arrangement of devices (nodes) and communication links in a computer network. It defines how computers, printers, and other devices are connected and how data flows between them. Different topologies are used depending on network size, reliability requirements, and cost considerations. The four common types of network topologies are Bus, Star, Ring, and Mesh. 1. Bus Topology: In a Bus topology, all devices are connected to a single central cable called the backbone. Data transmitted from a node travels along the bus until it reaches the intended receiver. Characteristics:
- All devices share a single communication line.
- Terminators are placed at both ends of the cable to prevent signal reflection.
- Data travels in both directions along the bus.
- Simple and inexpensive to install.
- Requires less cable compared to other topologies.
- Suitable for small networks.
- If the backbone cable fails, the entire network stops working.
- Difficult to troubleshoot.
- Network performance decreases as the number of devices increases.
- Each device has a dedicated cable connection to the central hub.
- The hub manages and controls data transmission.
- Easy to install and manage.
- Failure of one node does not affect the rest of the network.
- Easy to detect and isolate faults.
- If the central hub fails, the entire network becomes inactive.
- Requires more cable than bus topology.
- Higher installation cost.
- Each node acts as a repeater to transmit signals to the next node.
- Data travels through each device until it reaches the intended node.
- Data packets travel in an orderly manner.
- Reduced chances of data collision.
- Equal access for all devices.
- Failure of a single device can disrupt the entire network.
- Difficult to add or remove devices.
- Troubleshooting can be complex.
- Multiple paths exist between nodes.
- Data can travel through several alternative routes.
- Highly reliable and fault tolerant.
- Failure of one link does not affect the entire network.
- Provides high security and privacy.
- Very expensive due to large number of cables and ports.
- Complex installation and configuration.
- Not practical for large networks.
02
PYQ 2026
medium
computer-applications ID: pseb-xii
Define the role of network devices like Modems, Routers, Gateways, and Switches.
Official Solution
Correct Option: (1)
Concept: Network devices are hardware components used to connect computers and other devices in a network. They control the transmission of data, manage network traffic, and ensure communication between different networks and devices. 1. Modem (ModulatorβDemodulator): A modem is a device that converts digital signals from a computer into analog signals for transmission over communication lines such as telephone cables, and converts incoming analog signals back into digital form. Role of a Modem:
- Enables computers to connect to the internet.
- Converts digital signals to analog signals and vice versa.
- Used in DSL, cable, and telephone network connections.
- Connects different networks such as a home network and the internet.
- Determines the best path for data packets.
- Manages network traffic and prevents congestion.
- Allows communication between networks with different protocols.
- Translates data formats and communication rules.
- Often used to connect local networks to external networks.
- Connects computers, printers, and other devices in a LAN.
- Sends data only to the intended destination device.
- Improves network efficiency and reduces collisions.
03
PYQ 2026
medium
computer-applications ID: pseb-xii
Differentiate between guided (Twisted pair, Fiber-optic) and unguided (Radio, Microwave, Infrared) transmission media.
Official Solution
Correct Option: (1)
Concept: Transmission media refers to the physical path through which data travels from the sender to the receiver in a communication network. It can be broadly classified into two categories:
- Guided Transmission Media (Wired): Signals travel through a physical path such as cables.
- Unguided Transmission Media (Wireless): Signals propagate through free space using electromagnetic waves.
- Widely used in telephone networks and LANs.
- Available as UTP (Unshielded Twisted Pair) and STP (Shielded Twisted Pair).
- Supports moderate data transmission speeds.
- Low cost and easy to install.
- Flexible and lightweight.
- Suitable for short-distance communication.
- Limited bandwidth.
- Susceptible to electromagnetic interference.
- Very high bandwidth and data transmission speed.
- Long-distance communication capability.
- Immune to electromagnetic interference.
- Extremely high data transmission rate.
- Secure communication with minimal signal loss.
- Suitable for backbone networks and internet infrastructure.
- Expensive installation and maintenance.
- Fragile compared to copper cables.
- Used in radio broadcasting, mobile communication, and wireless networks.
- Omnidirectional transmission.
- Covers large geographical areas.
- No physical wiring required.
- Prone to interference and noise.
- Lower security compared to wired communication.
- Requires line-of-sight communication.
- Often used in satellite communication and cellular networks.
- High data transmission capacity.
- Suitable for long-distance communication.
- Affected by weather conditions.
- Requires careful alignment of antennas.
- Commonly used in remote controls, wireless keyboards, and short-range device communication.
- Signals cannot penetrate walls.
- Secure communication since signals remain confined to a room.
- Low interference with other wireless systems.
- Limited range.
- Requires direct line-of-sight.
04
PYQ 2026
medium
computer-applications ID: pseb-xii
Explain the functions of common network protocols: HTTP, FTP, SMTP, and TCP/IP.
Official Solution
Correct Option: (1)
Concept: A network protocol is a set of rules that governs how data is transmitted and received over a computer network. Protocols define the format, timing, sequencing, and error control of data communication between devices. 1. HTTP (Hypertext Transfer Protocol): HTTP is a protocol used for transferring web pages and other resources on the World Wide Web between a client (web browser) and a web server. Functions of HTTP:
- Allows web browsers to request web pages from servers.
- Transfers hypertext documents such as HTML files.
- Supports communication between clients and web servers.
- Enables uploading and downloading of files between systems.
- Provides file management operations such as rename, delete, and move.
- Commonly used for transferring large files over the internet.
- Transfers outgoing emails from the sender to the mail server.
- Routes emails between different mail servers.
- Works with other protocols like POP3 or IMAP for receiving emails.
- TCP ensures reliable and error-free delivery of data.
- IP handles addressing and routing of data packets.
- Enables communication between different networks across the internet.