Chapter:14 | Introduction to Data Communication and Network

 

Chapter:14 | Introduction to Data Communication and Network

Write very short answer of the following questions:

a. Is half duplex one way communication?

Ans: Yes, half duplex is one way communication.

b. Which was the first computer network of the world?

Ans: The first computer network in the world is considered to be the ARPANET (Advanced Research Projects Agency Network).

c. Which network device joins multiple computers together?

Ans: A network switch is a device that joins multiple computers together in a local area network (LAN).

d. What is protocol?

Ans: A protocol is a set of rules or standards that define how communication or actions should happen between systems, devices, or people.

e. Define cloud computing.

Ans: Cloud computing means storing and accessing data and programs over the internet instead of our computer’s hard drive.

f. What is the use of VPN while browsing the internet?

Ans: A VPN (Virtual Private Network) is used while browsing the internet to increase privacy, security, and access control.

g. Which is the fastest media in which data are transmitted according to the speed of light?

Ans: Optical fiber, utilizing light signals, provides the fastest data transmission medium approaching the speed of light.

h. Which network topology places hub at the center?

Ans: The network topology that places a hub at the center is typically the "Star" topology.

i. Is email faster and cheaper than postal mail?

Ans: Yes, email is faster and cheaper than postal mail.

j. Write any two popular search engine.

Ans: google and bing  are two popular search engine.

Write short answer of the following questions:

a. Write any two advantages of computer network.

Ans: Any two advantages of computer network are:

·        Data and information can be shared.

·        Data processing is economic and faster.

b. What is meant by network topology?

Ans: Network topology is the interconnection pattern of computers in the network. It is the physical layout of the terminals, links and computers in the network.

c. List any four common topologies.

Ans: Any four common topologies are:

1.     Bus topology

2.     Star topology

3.     Ring topology

4.     Mesh topology

d. Draw and explain about bus topology.

Ans: Bush topology is a type of network topology in which, all the computers are connected to a common cable called bus or trunk. This is simple and easy to install but if the common cable breaks it effect the whole network.

e. Differentiate between star and ring topology.

Ans: 

Star topology	Ring topology
1. Star topology connects devices to a central hub.	1. ring topology links devices in a circular chain.
2. Star topology is easy to set up and manage, suitable for small to medium-sized networks.	2.  Ring topology is less common due to complexity, but it can be more resilient as data travels through multiple devices.
3. If the hub fails, the whole network can be affected.	3. Failure of any single device can disrupt the entire network.

f. List its any four services of internet.

Ans: The four service of internet are:

1.     Email: Send and receive messages electronically (e.g., Gmail, Outlook).

2.     World Wide Web (WWW): Access websites and online content.

3.     File Sharing: Share and download files (e.g., via FTP, cloud storage).

4.     Online Communication: Video calls, chats, and social networking (e.g., Zoom, WhatsApp).

g. What is web browser? Name any two common browser software.

Ans: A web browser is a software application used to access and display websites on the Internet.  Any two common browser software are : Google Chrome and Mozilla Firefox.

h. What is ISP? List any two popular ISPs of Nepal.

Ans: ISP stands for Internet Service Provider. It's a company that provides internet service to users. Nepal Telecommunication (NTC) and World link are the two popular ISPs of Nepal.

i. List the components of data communication.

Ans: The components of data communication are:

1. Message

2. Sender

3. Receiver

4. Medium or communication Channel

5. Encoder and Decoder

Long Question

a.     What is Computer network? Explain the types of computer network.

Ans: A computer network is a system of interconnected devices (computers, servers, or other hardware) that communicate and share resources using communication protocols over a medium such as cables, Wi-Fi, or fiber optics.

Types of Computer Networks

1.     Local Area Network (LAN):

·        Scope: Limited to a building or campus.

·        Example: Office or home networks.

·        Use: File sharing, printer access.

2.     Metropolitan Area Network (MAN):

·        Scope: Covers a city or town.

·        Example: Cable TV networks.

·        Use: Municipal connectivity.

3.     Wide Area Network (WAN):

·        Scope: Spans large areas, such as countries or continents.

·        Example: The internet.

·        Use: Long-distance communication.

b.     Define internet and write the role and importance of internet in today’s world.

Ans: The Internet is a vast global network of interconnected devices and networks that communicate using standard protocols such as TCP/IP. It facilitates resource sharing, communication, and access to information worldwide.

Role and Importance of the Internet in Today’s World:

·        Communication: Enables instant communication via email, messaging apps, and video calls.

·        Education: Provides access to online learning platforms, resources, and research materials.

·        Business: Supports e-commerce, online banking, and global trade.

·        Entertainment: Offers streaming services, gaming, and social media.

·        Healthcare: Facilitates telemedicine, patient monitoring, and information sharing.

·        Information Sharing: Access to vast repositories of knowledge.

c.      What is network architecture? Explain the types of network architecture with their merits and demerits.

Ans: The framework or layout of a computer network, including the design, structure, and protocols used to enable communication and resource sharing called Network architecture.

Types of Network Architecture

1.     Peer-to-Peer (P2P):

All devices have equal status and share resources directly.

Merits:

·        Easy to set up.

·        Cost-effective.

·        No central server needed.

Demerits:

·        Limited scalability.

·        Less secure.

·        Difficult to manage in larger networks.

2.     Client-Server Architecture:

Devices (clients) access resources through a centralized server.

Merits:

·        Centralized control.

·        High security.

·        Scalable for large networks.

Demerits:

·        Expensive setup.

·        Server dependency.

·        Complex maintenance.