Basics OF Networking

Basics OF Networking 

What is Network ?

A computer Network or data Network is a Telecommunications Work which allows computers to exchange data. In computer networks, networked computing devices exchange data with each other using a data link. The connections between nodes are established using either cable media or wireless media.

• Interconnection of two or more devices is called as a Network.
• The Communication between two or more interconnected devices is called networking.
• An internetwork is a connection of two or more network.
• Internetworking means communication between different networks.

Types of Network ?

• LAN-  Local Area Networks are used to connect networking devices that are in a very close geographic area such as a floor of a building, a building itself or with in a campus.
• MAN- Metropolitan Area Network are used to connect networking devices that may span around the entire city.
• WAN- Wide area networks which connects two or more LANs present at different geographical locations.

LAN Network

Man Network

WAN Network

Basic Requirements to Form a Network.

• NIC ( Network Interface Card ) also called as LAN card.
• Media 
• Networking device like ( Hub,Switch,Router etc. )
• Protocols 
• Logical Address ( IP Address )

NIC(Network Interface Card)

• NIC is the interface between the computer and the network.
• It is also known as the LAN card or Ethernet Card.
• Ethernet Card have a unique 48 bit address called as MAC (Media access Control) Address. MAC Address is also called as physical address or hardware address. The 48bit MAC address is represented as 12 Hexa-decimal digits. Example :0 0 1 6.D 3 F C. 6 0 3 F
• Network card are available in Different Speed.
• Ethernet ( 10 Mbps)
• Fast Ethernet ( 100 Mbps)
• Gigabit Ethernet (1000 Mbps)

Media

The purpose of media is to transport bits from one machine to another.

Media Is of 2 type:-

• Guided 
• Unguided

Guided media Is also of 3 types :-

1. Co-axial 
2. Twisted pair 
3. Fiber

Unguided Media is of 2 types :-

1. Infrared 
2. RF

Types of twisted Pair Cables

Category                                DTR                       Purpose                          Connector

CAT1                                    1 Mbps                  Telephones                            RJ11

CAT2                                    4 Mbps                                                                RJ11

CAT3                                   10 Mbps                 Ethernet                                RJ45

CAT4                                   16 Mbps                                                               RJ45

CAT5                                   100 Mbps               Fast Ethernet                        RJ45

CAT5                                   500 Mbps                                                             RJ45

CAT6                                  1000 Mbps              Gigabit Ethernet                    RJ45

Topology

Topology is a physical layout of the system connected in a network.

Different types of Topology are:

• Bus
• Ring
• Mesh
• Star

Bus Topology

• In bus topology all devices are connected to a single cable or backbone.
• It support half duplex communication.
• A break at any point along the backbone will result in total network Failure.

Ex:

Ring Topology

• In Ring topology each computer or device is connected to its neighbor forming a Loop.
• Failure of a single Device or a break anywhere in the cable cause the full network to stop communicating.

                                                                     Ex:

Mesh Topology

• In mesh topology each device is directly connected to all other device.
• The disadvantage is the number of NIC's required on each device and the complex cabling.

Ex:

Start Topology

• The most commonly used topology.
• It consist of one centralized device which can be either a switch or a hub.
• The device connect to the various ports on the centralized devices.

Ex:

Networking Devices 

The various types of Networking Devices are:

• Hub
• Switch
• Router

Hub / Repeater

• It is not an Intelligent device.
• It works with bits.
• Uses broadcast for communication.
• Bandwidth is shared.
• Half-duplex communication.

Ex:

Switch

• It is an Intelligent Device.
• It maintains MAC address table ( Hardware address )
• Each port of the switch has fixed bandwidth.
• It works with flooding and Unicast
• Supports full duplex communication. 

Ex:

Router

• It is an Intelligent device.
• It works with logical addressing (i.e IP, IPX, Apple Talk)
• It work with Fixed bandwidth. 

Ex:

 If You Like My post Please Review My Blog In Comments .

________________________________Thank You ________________________________