What are Intranets and Extranets in Corporate Portals?

Businesspeople in cubicles,computers connected by stream of blue light
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An intranet is a generic term for a collection of private computer networks within an organization. An intranet uses ​network technologies as a tool to facilitate communication between people or workgroups to improve the data sharing capability and overall knowledge base of an organization's employees.

Intranets utilize standard network hardware and software technologies like Ethernet, Wi-Fi, TCP/IP, Web browsers and Web servers.

An organization's intranet typically includes Internet access but is firewalled so that its computers cannot be reached directly from the outside.

An extranet is a computer network that allows controlled access from the outside for specific business or educational purposes. Extranets are extensions to, or segments of, private intranet networks built by businesses for information sharing and e-commerce.

Many schools and non-profit groups have deployed them also, but an intranet is still seen primarily as a corporate productivity tool. A simple intranet for a small business consists of an internal email system and perhaps a message board service. More sophisticated intranets include internal Web sites and databases containing company news, forms, and personnel information.