Network Topologies

Topology :- Topology defines the way a network is created i.e. the way the computers are connected with each other.The following are the types of topologies :-
1. Star
2. Bus
3. Ring
4. Mesh

Star Topology :- It is named as star as it looks like a star when the computers are connected with each other. Its central point is either a HUB or a Switch.
1. In this UTP(Unshielded Twisted Pair) cables are used.
2. RJ-45 connectors are used.
3. No need of a repeater as the port of the Hub works like repeater.
4. This topology is used mostly in todays network.

Bus Topology :-
1. In this coaxial wires are used.
2. T- Connectors are used.
3. Failure at one point damage the whole network.

Ring Topology :-

1.UTP wires are used.

2.RJ-45 connectors are used.

3.Repeaters are used.

4. Failure at one point doesnt break the whole network.

Mesh Topology :-
In this topology all the computers are connected with each other directly there isn't any hub or switch.
So, in this topology cost of wires and network cards is very much . This topology is good for two or three computer more than that cost is very much.If link between two computers break it will not damage the whole network.

  

Types of Network

LAN :- LAN stands for Local Area Network.It is a collection of nodes together in a limited geographical area such as home , school , in a building etc.

MAN :- MAN stands for Metropolitan Area Network.It is bigger than LAN but smaller than WAN(Wide Area Network).It is used by telecommunication & tele-marketing companies like BSNL , Reliance etc.

WAN :- WAN stands for Wide Area Network. It is used to connect two or more similar or dissimilar networks together like Internet.

Networks

Computer is an electronic device that takes input from the user, processes it and gives the output.The computer hardware refers to those parts of a computer system that have a physical existence i.e. we can touch and see e.g. monitor, keyboard, mouse, printer etc.The computer software refers to that part of a computer that only has a logical existence i.e. we cannot touch and feel computer software e.g. operating system such as WIN 98, DOS and UNIX, application softwares such as MS-OFFICE, Corel Draw, Photoshop etc. Computer software is also referred to as a set of programs.

COMPUTER NETWORKS:A computer network is a collection of two or more computers that can communicate with each other.Aims of Computer Network:-

1. DATA SHARING: - On a network computers can share data between each other.
2. RESOURCE SHARING :- Resources on the network are like printers, CD-ROM drives, CD-WRITERS, etc that can be shared between all the computers on the network, thereby reducing cost of resources for each and every computer package.
3. SECURITY :- Security means restricting or controlling unauthorized access.