An extranet is part of an intranet that is extended to outside users to share part of the private information. An extranet could also be described as two or more intranets with network connectivity. Generally, and as with intranets, an extranet will be based on Internet Protocols.

An argument could be made that "Extranet" is just a buzzword for describing what institutions have been doing for decades, that is, interconnecting to each other to create private networks for sharing information. During the late 1990s and early 2000s, several industries started to use the term "extranet" to describe central repositories of shared data made accessible via the web only to authorised members of particular work groups. Specially secured extranets are used to provide virtual Data room services to companies in a number of sectors.

There are a variety of commercial Extranet applications. Some of which are for pure file management, others include broader collaboration tools and project management tools.

Check out the links provided here for more information about extranet.

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