ITI COPA (Computer Operator & Programming Assistant) – Basic Notes

Topic-

Communicating in a Connected World

1. Introduction: Communicating in a Connected World

In today’s digital era, computers and devices do not work alone. They are connected with each other to share information, resources, and services. This interconnected environment is called a connected world. Communication between computers, mobile devices, servers, and other digital equipment happens through computer networks.

For ITI COPA students, understanding network communication is very important because networking is widely used in offices, industries, banks, schools, hospitals, government departments, and the Internet.

2. Concept of Network Communication

What is Network Communication?

Network communication is the process of exchanging data and information between two or more devices using a communication medium and set of rules (protocols).

Key Elements of Network Communication

Sender – Device that sends data
Receiver – Device that receives data
Message/Data – Information being transmitted
Medium – Path through which data travels
Protocol – Rules for communication

Importance of Network Communication

Sharing files and data
Sharing hardware like printers and scanners
Communication via email, chat, video calls
Internet access
Centralized data management

3. Principles of Communication

Communication in networks follows certain principles to ensure correct and reliable data transfer.

Basic Principles

Accuracy – Data should not be altered
Reliability – Data must reach destination
Speed – Fast transmission
Security – Protection from unauthorized access
Scalability – Ability to grow with demand

Modes of Communication

Simplex – One-way communication (TV broadcast)
Half Duplex – Both directions, but one at a time (Walkie-talkie)
Full Duplex – Both directions simultaneously (Telephone)

4. Local Networks (LAN – Local Area Network)

What is a Local Network?

A Local Area Network (LAN) is a network that connects computers and devices within a small geographical area, such as:

Home
Office
School
Laboratory

Characteristics of LAN

High data transfer speed
Low cost
Limited geographical area
Privately owned
Easy to manage

Examples of LAN

Computer lab network
Office network
Home Wi-Fi network

5. Communicating on a Local Network

Devices on a LAN communicate with each other using:

Network Interface Cards (NIC)
Switches
Ethernet cables or Wi-Fi
TCP/IP protocol

Communication Process in LAN

Data is broken into packets
Packets are addressed to destination
Switch forwards data to correct device
Receiving device reassembles data

6. Roles of Devices in a Network

Each device in a network performs a specific role.

1. End Devices

Computers
Laptops
Smartphones
Printers

Role:
Send and receive data

2. Network Devices

Switch
Router
Hub
Access Point

Role:
Manage and control data flow

3. Server Devices

File server
Web server
Database server

Role:
Provide services to clients

7. Introduction to LAN Devices

1. Network Interface Card (NIC)

Connects device to network
Has unique MAC address

2. Hub

Basic networking device
Broadcasts data to all devices
Less secure and inefficient

3. Switch

Intelligent networking device
Sends data only to intended device
Faster and more secure than hub

4. Router

Connects different networks
Routes data packets
Connects LAN to Internet

5. Modem

Converts digital signals to analog and vice versa
Used for Internet connectivity

6. Wireless Access Point (AP)

Provides wireless connectivity
Used in Wi-Fi networks

8. How Do Ethernet Networks Work?

What is Ethernet?

Ethernet is the most commonly used LAN technology that defines how devices format and transmit data over wired networks.

Ethernet Components

Ethernet cable (UTP)
Switch
NIC
Ethernet protocol

Ethernet Communication Process

Data divided into frames
MAC address used for identification
Switch forwards frames
Error detection ensures accuracy

Advantages of Ethernet

High speed
Reliable
Secure
Low interference

9. How Are Networks Built?

Steps to Build a Network

Identify requirements
Select network type (LAN, WLAN)
Choose devices
Choose transmission media
Configure IP addressing
Test network connectivity

Network Topologies

1. Star Topology

Central switch
Easy to manage
Most common

2. Bus Topology

Single backbone cable
Low cost
Rarely used now

3. Ring Topology

Circular data flow
Difficult to manage

4. Mesh Topology

Multiple connections
High reliability
Expensive

10. Routing Across Networks

What is Routing?

Routing is the process of selecting the best path for data packets to travel from source to destination across multiple networks.

Role of Router

Determines best path
Uses IP addresses
Connects LAN to WAN

Routing Table

Stores path information
Used by router to forward data

11. Interaction Between End-User Devices, Local Networks and Internet

End-User Devices

Laptop, smartphone, PC

Local Network

Connects devices internally

Internet

Global network of networks

How They Interact

User sends request (website)
Request travels through LAN
Router forwards request to ISP
Data travels across Internet
Response returns to user

12. What Does a Home Network Look Like?

Components of Home Network

ISP connection
Modem
Wi-Fi Router
Devices (PC, phone, TV)

Home Network Features

Wired + Wireless devices
Shared Internet access
File and printer sharing

13. How Does Wi-Fi Work?

What is Wi-Fi?

Wi-Fi is a wireless networking technology that uses radio waves to provide network and Internet access.

Wi-Fi Components

Wireless router
Access point
Wireless NIC

Wi-Fi Working Process

Router sends radio signals
Device receives signal
Data is transmitted wirelessly
Encryption ensures security

Wi-Fi Standards

802.11a
802.11b
802.11g
802.11n
802.11ac

Advantages of Wi-Fi

Mobility
Easy installation
Cost-effective

14. Internetworking Devices

Internetworking devices connect multiple networks together.

1. Router

Network-layer device
Uses IP address

2. Gateway

Connects different network types
Converts protocols

3. Bridge

Connects two LAN segments
Reduces traffic

15. Importance of Networking Knowledge for COPA Students

Essential office skill
Used in system administration
Required for IT support roles
Important for CBT exams
Enhances employability

MCQ Questions (40 Questions – CBT Exam)

1. A computer network is used to:

A) Increase file size
B) Share resources
C) Delete data
D) Install OS
Ans: B

2. LAN stands for:

A) Large Area Network
B) Local Area Network
C) Logical Area Network
D) Linked Area Network
Ans: B

3. LAN covers:

A) Country
B) City
C) Small area
D) World
Ans: C

4. Which device connects computers to network?

A) CPU
B) RAM
C) NIC
D) ROM
Ans: C

5. Hub sends data to:

A) One device
B) All devices
C) Router
D) Server
Ans: B

6. Switch sends data to:

A) All devices
B) Intended device
C) Internet
D) Server only
Ans: B

7. Router is used to:

A) Store data
B) Connect networks
C) Print documents
D) Scan images
Ans: B

8. Ethernet is a:

A) OS
B) LAN technology
C) Protocol only
D) Hardware
Ans: B

9. MAC address is:

A) IP address
B) Unique hardware address
C) Website address
D) Email address
Ans: B

10. Which topology uses central device?

A) Bus
B) Ring
C) Star
D) Mesh
Ans: C

11. Wi-Fi uses:

A) Cables
B) Light waves
C) Radio waves
D) Infrared
Ans: C

12. Which device provides Wi-Fi?

A) Modem
B) Switch
C) Access Point
D) Printer
Ans: C

13. Home network mainly uses:

A) WAN
B) MAN
C) LAN
D) PAN
Ans: C

14. Internet is a:

A) LAN
B) WAN
C) MAN
D) PAN
Ans: B

15. ISP stands for:

A) Internet Security Protocol
B) Internet Service Provider
C) Internal System Program
D) International Server Point
Ans: B

16. Protocol defines:

A) Hardware design
B) Communication rules
C) Storage space
D) Software size
Ans: B

17. Which device routes data?

A) Hub
B) Switch
C) Router
D) Bridge
Ans: C

18. Gateway is used to:

A) Connect similar networks
B) Connect different networks
C) Store data
D) Encrypt data
Ans: B

19. Which is an end-user device?

A) Router
B) Switch
C) Laptop
D) Hub
Ans: C

20. Network speed in LAN is:

A) Low
B) Very slow
C) High
D) Variable
Ans: C

21. Which is a wired medium?

A) Wi-Fi
B) Bluetooth
C) Ethernet cable
D) Radio
Ans: C

22. Full duplex means:

A) One-way
B) Both ways one at a time
C) Both ways simultaneously
D) No communication
Ans: C

23. Router uses:

A) MAC address only
B) IP address
C) File name
D) Port name
Ans: B

24. Network topology defines:

A) Speed
B) Physical arrangement
C) Cost
D) Protocol
Ans: B

25. Which topology is most reliable?

A) Bus
B) Ring
C) Mesh
D) Star
Ans: C

26. Data sent over network is broken into:

A) Files
B) Frames/Packets
C) Folders
D) Tables
Ans: B

27. Which device reduces network traffic?

A) Hub
B) Switch
C) Modem
D) Cable
Ans: B

28. Wireless network is called:

A) LAN
B) WAN
C) WLAN
D) MAN
Ans: C

29. Which standard is related to Wi-Fi?

A) IEEE 802.11
B) IEEE 802.3
C) TCP/IP
D) HTTP
Ans: A

30. Internet connects:

A) Computers only
B) Networks
C) Printers
D) Servers only
Ans: B

31. Which device converts signals?

A) Router
B) Switch
C) Modem
D) Hub
Ans: C

32. Communication accuracy depends on:

A) CPU speed
B) Protocols
C) RAM
D) Monitor
Ans: B

33. LAN is usually owned by:

A) Government
B) Private organization
C) ISP
D) Public
Ans: B

34. Wi-Fi security uses:

A) Encryption
B) Compression
C) Fragmentation
D) Routing
Ans: A

35. Bridge operates at:

A) Physical layer
B) Data link layer
C) Network layer
D) Application layer
Ans: B

36. End devices communicate using:

A) NIC
B) RAM
C) CPU
D) ROM
Ans: A

37. Which device provides Internet sharing?

A) Hub
B) Switch
C) Router
D) Printer
Ans: C

38. Communication medium can be:

A) Wired or wireless
B) Only wired
C) Only wireless
D) Only optical
Ans: A

39. A connected world means:

A) Offline computers
B) Isolated devices
C) Networked devices
D) Single computer
Ans: C

40. Networking knowledge is important for:

A) Only programmers
B) Only hardware engineers
C) IT professionals
D) Artists
Ans: C

ITI (Trade - COPA) Day-14