Computer Networks Notes | Basic Computer Engineering | RGPV BTech First Year

Computer Networks

Computer Network दो या दो से अधिक Computers तथा Devices का ऐसा समूह होता है जो Communication Links के माध्यम से आपस में जुड़े होते हैं और Data तथा Resources को Share करते हैं। आधुनिक समय में Networking Technology Banking, Education, Healthcare, Cloud Computing तथा Business Operations का आधार बन चुकी है।

Introduction

पहले Computers स्वतंत्र रूप से कार्य करते थे और Data Sharing कठिन था। Networking Technology के विकास के बाद Computers को आपस में जोड़ना संभव हुआ। Computer Networks के माध्यम से Files, Printers, Applications तथा Internet Connections को Share किया जा सकता है।

आज लगभग सभी Organizations अपने Operations के लिए Networks का उपयोग करती हैं। Computer Networks Communication को तेज, सुरक्षित तथा प्रभावी बनाते हैं।

Definition of Computer Network

Computer Network Interconnected Devices का एक समूह है जो Communication Protocols का उपयोग करके Data Exchange करते हैं।

Computer Network = Interconnected Devices + Communication Protocols

Objectives of Networking

Resource Sharing
Data Communication
Information Exchange
Remote Access
Cost Reduction
Centralized Management

Characteristics of Computer Networks

High Connectivity
Data Sharing
Reliability
Scalability
Security Support
Resource Optimization

Types of Computer Networks

LAN (Local Area Network)
MAN (Metropolitan Area Network)
WAN (Wide Area Network)

1. LAN (Local Area Network)

LAN छोटे क्षेत्र जैसे Office, School या Building में Computers को जोड़ने के लिए उपयोग किया जाता है।

High Speed
Low Cost
Easy Management

2. MAN (Metropolitan Area Network)

MAN एक शहर या बड़े क्षेत्र में Network Connectivity प्रदान करता है।

City Wide Coverage
Moderate Cost
High Capacity

3. WAN (Wide Area Network)

WAN बड़े भौगोलिक क्षेत्रों में स्थित Networks को जोड़ता है।

Global Connectivity
Internet Based Communication
Large Coverage Area

Network Topologies

Bus Topology
Star Topology
Ring Topology
Mesh Topology
Tree Topology

Topology	Advantage
Star	Easy Maintenance
Bus	Low Cost
Ring	Orderly Communication
Mesh	High Reliability

Network Devices

Device	Function
Hub	Broadcast Data
Switch	Forward Data Efficiently
Router	Connect Different Networks
Modem	Internet Connectivity

Network Protocols

TCP/IP
HTTP
HTTPS
FTP
SMTP

Protocols Communication के नियम निर्धारित करते हैं।

Advantages of Computer Networks

Resource Sharing
Fast Communication
Data Backup
Cost Saving
Centralized Control
Remote Access

Limitations

Security Risks
Network Failure
Maintenance Cost
Virus Propagation

Applications of Computer Networks

Internet Access
Email Communication
Cloud Computing
Online Education
E-Commerce
Video Conferencing
Banking Systems
Healthcare Systems

LAN vs MAN vs WAN

Feature	LAN	MAN	WAN
Coverage	Small Area	City	Worldwide
Speed	High	Medium	Variable
Cost	Low	Medium	High

Industrial Importance

Cloud Infrastructure
Enterprise Communication
Banking Networks
Telecommunication Systems
Remote Work Solutions
Data Centers

Viva Questions

What is a Computer Network?
What is LAN?
What is MAN?
What is WAN?
What is a Router?
What is a Switch?
What is Network Topology?
What is TCP/IP?
Difference between Hub and Switch?
What are Network Protocols?

Exam Oriented Important Questions

Define Computer Network.
Explain Types of Computer Networks.
Discuss Network Topologies.
Explain Network Devices.
Differentiate between LAN, MAN and WAN.
What are Network Protocols?
Describe Applications of Computer Networks.

Conclusion

Computer Networks आधुनिक Information Technology का आधार हैं। ये Data Sharing, Resource Utilization तथा Global Communication को संभव बनाते हैं। Networking का ज्ञान प्रत्येक Engineering Student के लिए अत्यंत आवश्यक है क्योंकि वर्तमान Digital Infrastructure पूरी तरह Networks पर आधारित है।