Network an introduction

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IN THIS ARTICLE

(a) What is Network?
(b) Types of Network
(c) What is Network Connection?
(d) Types of Network Connections
(e) What is Network Protocol?
(f) What is Network Packets?
(g) What is Network Topology?
(h) Types of Network Topology

A Network is a group of  two or more interconnected devices for information or resource sharing and communication. The interconnected devices can be laptop, PC, server, router, switches, printer, smart phone and tablet etc.


Types of Network

(A) LAN (Local Area Network): It is used to cover a limited or small area like home, office and campus.

(B) MAN ( Metropolitan Area Network): It covers a single geographical area and within that area connects different LANs from different locations like a city or large campus.

(C) WAN (Wide Area Network): It is used to cover larger geographical area and connects different LANs from different locations like cities, regions and countries.

For example: Internet


Connections

In networking, "connections" generally refer to the establishment of communication links between two or more devices or systems. These connections are used for data exchange and communication in computer networks.

There are mainly two types of connections exists in network physical or wireless connections.

(A) Physical connections

Physical connections in wired networks are made using cables, like Ethernet cables. To establish a network, these connections physically join components such as servers, routers, switches, and PCs.

(a) Ethernet connection: establishes connections between devices using Ethernet cables.

(b) Fiber Optic Connection: For fast, long-distance connections, optical fibers are used.

(B) Wireless connections

Wi-Fi or cellular networks are frequently used to establish connections wirelessly, eliminating the need for physical wires.


Protocols

Networks use communication protocols to deal with data transmission and receiving.

Examples are TCP/IP (Transmission Control Protocol/Internet Protocol) for the internet and HTTP (Hypertext Transfer Protocol) for web communication.


Network Packets

The data transfer over a communication channel occurs in the form of a data packet which is a basic unit of large messages.

These data packets have three parts header, payload and trailer.

The Header contains a source address, a destination address, protocol, and packet number.

The payload contains actual data being transmitted by the packet.

The trailer contains a few bits that inform the receiving device that it has reached to the end of the packet, as well as a Cyclic Redundancy Check (CRC), which enables the computer to determine if all the packets were received completely.


Topology

Network topology refers to the physical or logical layout of devices and connections in a network.

Examples are star, bus, ring, and mesh, each having their advantages and disadvantages.


Star Topology:  A network configuration in which all devices are directly connected to a central hub or switch.

Bus Topology:  A network configuration in which all devices are connected to a single central cable or bus. The devices are connected to this cable at various points and cable serves as a communication backbone.

Ring Topology:  A network configuration in which each device is connected to other two devices and forming a closed loop.

Mesh Topology: A network configuration in which each device is connected to every other devices.

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