Data communication network

 

INTRODUCTION

Data communications refers to the transmission of this digital data between two or more computers and a computer network or data network is a telecommunications network that allows computers to exchange data. The physical connection between networked computing devices is established using either cable media or wireless media. The best-known computer network is the Internet.

Categories

Computer Networks are classified into many categories based on their respective attributes. These includes:

• Geographical span
• Inter-connectivity
• Administration
• Architecture

Geographical Span

Geographically a network can be seen in one of the following categories:

• It may be spanned across your table, among Bluetooth enabled devices. Ranging not more than few meters.
• It may be spanned across a whole building, including intermediate devices to connect all floors.
• It may be spanned across a whole city.
• It may be spanned across multiple cities or provinces.
• It may be one network covering whole world.

Inter-connectivity

Components of a network can be connected to each other differently in some fashion. By connectedness we mean either logically or physically or both ways.

• Every single device can be connected to every other device on network, making the network mesh.
• All devices can be connected to a single medium but geographically disconnected, created bus like structure.
• Each device is connected to its left and right peers only, creating linear structure.
• All devices connected together with a single device, creating star like structure.
• All devices connected arbitrarily using all previous ways to connect each other, resulting in a hybrid structure.

Administration

From an administrator’s point of view, a network can be private network which belongs a single autonomous system and cannot accessed outside its physical or logical domain. Or a network can be a public network, which can be accessed by all.

Network Architecture

• There can be one or more systems acting as Server. Other being Client, request the Server to serve requests. Servers take and process request on behalf of Clients.
• Two systems can be connected Point-to-Point, or in other words back-to-back fashion. They both reside on same level and called peers.
• There can be hybrid network which involves network architecture of both the above types.

 

Network Applications

Computer systems and peripherals are connected to form a network provides bunch of advantages:

• Resource sharing such as printers and storage devices.
• Exchange of Information by means of eMails and FTP.
• Information sharing by using Web or Internet.
• Interaction with other users using dynamic web pages.
• IP phones
• Video Conferences
• Parallel computing
• Instant messeging

 

source link:http://www.tutorialspoint.com/data_communication_computer_network/index.htm