Extranets and Intranet

Over recent years, the terms intranet and extranet have established themselves firmly in the IT vocabulary. Even so, many people are still unsure about what exactly defines, or is defined by, either an intranet or an extranet.


The term intranet is commonly used to describe a web-based application or system that provides tools for groups of people to work together collaboratively. The key element of an intranet is that only people within an organization can access it. Intranets are typically hosted, maintained, and operated completely independently from an organization's external Web presence, even though some of the information provided through both mechanisms might be the same. An example of an intranet is shown in Figure 4

Figure 4 An example of an intranet.

Intranets are commonly identified by the following characteristics:

  • Limited access Access to an intranet is normally limited to users, or a sub-group of users, within the organization.

  • Browser based Most intranets operate as Web serverbased applications, and so are accessed through a Web browser.

  • Types of application Although no specific rules define what applications an intranet can host, the most common are collaborative, 'groupware' applications.