Internet, Intranet & Extranet

What is Internet ?

Internet is a global system of interconnected computer networks that use standard internet protocol suite to kink several devices worldwide. It is an international network of networks, linked by optical, wireless and electronic networking technologies which consists of business, public, educational and government networks.

It carries an extensive range of information, resources and services. It utilises –

IP Addressing Scheme
Transmission Control Protocol (TCP)
Peer2Peer (P2P) networks for file sharing and telephony

The main reasons for its establishment was to transmit data, share resources and communicate remotely.

Important Features –

It is spread over 65 Countries
There is no regulatory authority for internet therefore any one can access it
All computers on the internet communicate via IP/TCP protocol using a client/server architecture
A PC, Router, Browser and an Internet service provider are needed to connect to the Internet
The main uses are –File sharing, Program sharing, Hardware sharing, Multi-user activities, Communication and Reaching remote areas

It provides a variety of services such as – File Transfer, Electronic mail, Real-time broadcasting, E-commerce, Information resources etc.

Applications of Internet –

Communication – Email, Online chat, Telephony (Voice, fax, SMS, MMS), video conferencing, file sharing etc.
Remote login – A user can login to his/her concerned online account from anywhere in the world.
E-commerce – B2B, B2C, C2C portals,
Online Banking – Electronic fund transfer, Online account management
Entertainment – Movies, videos, online books, news etc.
Advertising – Banner ads, text ads, social media marketing etc.
Research and Development – Online surveys, private browsers, search engines
Online Education & Training – Online exams, tutorials, e-books, notes and lectures etc.
Stock Exchange and Trading
Social Networking and Blogging

Disadvantages –

Cyber Crime
Virus, Malware, Spamming
Phishing
Hacking
Adult and abusive content
Unrestricted medium
Theft of personal information and copyright issues
Online Fraud and terrorism

What is Extranet?

An extranet is a private network that uses Internet technology and the public telecommunication system to securely share part of a business’s information or operations with suppliers, vendors, partners, customers, or other businesses. An extranet can be viewed as part of a company’s intranet that is extended to users outside the company. It has also been described as a “state of mind” in which the Internet is perceived as a way to do business with other companies as well as to sell products to customers.

It is an extension of info system of the company to its partners outside. It uses internet protocols to link intranets over the public internet. It involve authentication via a username and password.

Uses of Extranet-

Exchange large volume of data
Share product catalogues
Collaborate with partners & peers
Joint training programs

What is Intranet ?

An intranet is a private network that is contained within an enterprise. It may consist of many interlinked local area networks and also use leased lines in the wide area network. Typically, an intranet includes connections through one or more gateway computers to the outside Internet. The main purpose of an intranet is to share company information and computing resources among employees. An intranet can also be used to facilitate working in groups and for teleconferences.

Typically, larger enterprises allow users within their intranet to access the public internet through firewall servers that have the ability to screen messages in both directions so that company security is maintained. When intranet is made accessible to customers, partners, suppliers, or others outside the company, it becomes an extranet.

It enhances existing communication between employees and provides a common knowledge and storage base. It provides access to company, data systems, technical documents etc.