What is Internet, What About Internet, Intranet, Extranet

INTERNET

The Internet is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a network of networks that consists of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and file sharing.

Internet is different from the World Wide Web (WWW) as the World Wide Web is a network of computers and servers created by connecting them through the internet. So, the internet is the backbone of the web as it provides the technical infrastructure to establish the WWW and acts as a medium to transmit information from one computer to another computer. It uses web browsers to display the information on the client, which it fetches from web servers.

The internet works with the help of clients and servers. A device such as a laptop, which is connected to the internet is called a client, not a server as it is not directly connected to the internet. However, it is indirectly connected to the internet through an Internet Service Provider (ISP) and is identified by an IP address, which is a string of numbers.

The internet is managed by ICANN (Internet Corporation for Assigned Names and Numbers) located in the USA. It manages IP addresses assignment, domain name registration, etc.

INTRANET

The intranet is a private network that belongs to a particular organization. It is designed for the exclusive use of an organization and its associates, such as employees, customers, and other authorized people. It offers a secure platform to convey information and share data with authorized users. Confidential information, database, links, forms, and applications can be made available to the staff through the intranet. So, it is like a private internet or an internal website that is operating within an organization to provide its employees access to its information and records. Each computer in intranet is identified by a unique IP (Internet Protocol) Address.

It is based on internet protocols (TCP/IP) and is protected from unauthorized access with firewalls and other security systems. The firewall monitors the incoming and outgoing data packets to ensure they don't contain unauthorized requests. So, users on the intranet can access the internet, but the internet users can't access the intranet if they are not authorized for it. Furthermore, to access the intranet, the authorized user is required to be connected to its LAN (Local Area Network).

EXTRANET

An extranet is a private network organization, which is actually the part of respective company’s intranet and its services are extended to users outside the company. It is a communication network that is based on internet protocols (TCP/IP). It provides controlled access to firm's intranet to its trading partners, customers, and other businesses.

An extranet service requires firewall server management in order to provide security and privacy.

The advantages of Extranet services are as follows :

It makes business (services) swift and faster.
It helps greatly in improving the business communication.
It helps in reducing the cost (especially in terms of stationery stuff).
It helps in improving the efficiency and confidence of the employees.
It reduces some big physical barriers (especially the geographical distance).

Major Fields Using Extranet :

Corporate houses
Government offices
Education centers

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