Introduction of Networking

Networking is the process of connecting one computer terminal with the others. A communication system that supports many users can be called a network or we can say network is a communication system, which interconnects many users who have something in common, either with respect to the type of data being sent or to the geographic areas that the users cover. Networks can be used between people, between people and computers, between computers and equipment or between computers. Today, organizations use networks in all possible ways. depending on the application, the network needs different speed, degree of reliability, and cost. One of the largest networks in the world is at the national aeronautics and space agency (NASA). This networks combine all of the worldwide space tracking stations, the NASA research facilities, and the NASA operational offices. Data from any location can be instantly sent to any other, as can memos, messages, and conversations.

Advantages of Computer Network :-

Computer networks provide many benefits. Some important benefits are :

· Computer networks make communication easy and fast between different users.

· Computer networks allow users to share data and software at the same time.

· Different network users can share peripheral devices such as printers, scanners, CD-Drives etc.

· It is easy for the users to backup important data and information.

Components Of Network :-

Network allow many user to access the shared data, software and hardware. As computer network basically requires hardware, medium and software to connect and to make communication between different computers.

Server :-

The main computer which provides services to the other computers in a network environment is called server. It also provides software and data to the client computer.

Workstation/Client :-

Workstation or client is a computer where a user can work. It takes services, access shared data and software.

Medium :-

A medium is a communication channel, which is used to connect different computers and devices in a network environment. It is used to move data from one device of the network to the other devices. Some examples of medium are fiber optics cable, Coaxial cable, satellite, blue tooth, radio waves etc.

Network Interface Card (NIC) :-

A network interface card makes physical connection between two different computers. This device is mounted on the motherboard of each computer. it is used to control the flow of data between two different computers.

HUB :-

A hub is a small device with multiple ports. It provides physical connection to the different devices of the network. Some hubs simply connect the devices but some hubs can regenerate or amplify a signal.

Repeater :-

A repeater is a device of network that regenerates the signal. it converts a weak signal to a strong on and sends to the computer in a long distance.

Software :-

Physical components are not sufficient to create a network environment and share the network resources. Network operating system is a group of programs, which are use to manage the resources on the network. Common network operating systems are windows NT, Windows 2000, Windows XP, Novell Netware etc.

Network Protocols

Network protocols are setup rules, which are followed to make communication between computers. Protocols are responsible to sends and receive data in computer networks. They are part of network operating system, which are used to conduct the network operations. A single network IP (transmission Control protocol/Internet protocol), NetBEUI (NetBIOS extended user interface), IPX/SPX (Internet work packed exchange/sequenced packet exchange) , HTTP (Hypertext transfer protocol) , POP (Post Office Protocol) etc.

Types of computer network :-

According to the geographical location and size, the computer networks are divided into 3 groups, they are :

a. LAN (Local Area Network)

b. MAN (Metropolitan Area Network)

c. WAN(Wide Area Network)

a. Local Area network (LAN)

Local area network (LAN) is a network system that covers very small area. The computers are connect in such a way that is enables them to communicate by cables or small wireless devices. Networks within a room or a small building or a school or a college area, a hospital or office are examples of local area networks. This type if network is setup to share their data and software. It is controlled and supervised by a person called network administrator.

b. Metropolitan Area Network (MAN)

A network within a town or city to share data, information other resources is called metropolitan area network (MAN). MAN is a network that connects different LANs a two different computers together. Networks between different branches of banks, different schools or colleges are examples of MAN. This type of network is controlled and supervised by a single organization or a group of organizations.

c. Wide Area Network (WAN)

WAN is network system, which connects to or more networks or two different computers connected together in large geographical area. For example, a company has its two different branches in two different cities. To share data and to communicate, they can use high-speed public telephone lines or wireless technologies. No single authority has right to control this type of network. It is controlled and managed by different organizations.

Models of Network :-

Networks can be categorized into three different models. They are : i) Centralized computing ii) client/server iii) peer-to-peer. Centralized computing model is used with mainframe or mini computer running with Unix operating system. Client/server and peer-to-peer are designed with personal computers.

a. Centralized computing network

In centralized computing network, the main computer is called host computer. Here, workstations have no processing capabilities; they are just use for input/output operations. The host computers runs and solves multiple jobs for workstations in an efficient manner. It may run with a powerful operating system called Unix or Linux.

b. Client/server Network

Client/server model of network is one of the powerful models, which consists of at least one server and one or more clients or workstations. Here, workstations or clients share the processing and storage work load with the central server. This model requires special software for the server and the workstations. It is suitable for a large organization because it distributes processing and storage work load among the available resources. In this model, the network administrator controls the rights and duties of the users.

c. Peer-to-peer network

peer-to-peer network is group of computers there function equally as servers and workstations. Here, the user works on a workstation and shares that workstation's resources with other computers. It is suitable for small offices and schools to share data, software, hard disk, printers etc. Operating systems such as windows 9x and later versions support peer-to-peer network. The main disadvantage of this model is that it provides less security to network users and resources.