What is the difference between intranet and extranet?
If you've ever worked in a large corporation, you've probably already worked with the intranet or extranet. In simple words, an Intranet is a private network and a database that is restricted and can only be accessed by company employees. An Extranet is accessible to outside contractors. In this article, we will explain to you what is the difference between intranet and extranet and how both of them function.
What is an intranet?
An intranet is a set of Internet services (for example, a web server) inside a local network, i.e., only accessible from workstations of a local network, or rather a set of well-defined networks that are invisible (or inaccessible) from the outside. It involves using Internet client-server standards (TCP/IP) protocols such as Web browsers (HTTP protocol-based client) and Web servers to create an information system inside an organization or enterprise.
An intranet is generally based on a three-tier architecture comprising:
- Clients (generally Web browsers);
- one or several application servers (middleware): a web server that makes it possible to interpret CGI, PHP, ASP, or other scripts and translate them into SQL queries to query a database;
- a database server.
In this manner, the client machines handle the graphical interface while the different servers handle the data. The network allows it to exchange queries and responses between clients and servers.
An intranet has several clients (the local network computers) and may comprise several servers. A large enterprise may, for example, have a web server for each service to provide an Intranet consisting of a federation web server linking the different servers managed for each benefit.
How helpful is the intranet?
An intranet within an enterprise makes it easy to make a wide variety of different documents available to employees, which provides centralized and coherent access to the enterprise's knowledge, which is referred to as capitalization of knowledge. In this manner, it is generally necessary to define the access rights of the Intranet users to the documents located thereon and, consequently, the authentication of such access rights to provide them personalized access to certain documents.
Documents (text, images, videos, sounds, etc.) can be available on an Intranet. In addition, an Intranet may provide an exciting groupware function, i.e., allow group work. Here are some of the functions which an Intranet may provide:
- Access to information regarding the enterprise (bulletin board)
- Access to technical documents
- Search engine for documentation
- Exchange of data among coworkers
- Staff roster
- Project management, decision-making aid, agenda, computer-aided engineering
- Discussion forum, distribution list, direct chat
- Videoconference
- Internet portal
An Intranet, therefore, favors communication within the enterprise and limits errors as a result of poor flow of information. The information available on the intranet must be updated to prevent version conflicts.
What are the advantages of an intranet?
An Intranet makes it possible to create an information system at a low cost (specifically, the cost of an Intranet may very well be limited to the cost of the material, its maintenance, and updating, with client workstations operating with free navigators, a server running under Linux with the Apache web service, and the database server MySQL).
On the other hand, considering the "universal" nature of the means in play, any type of machine can be connected to the local network, i.e., the intranet.
How to implement the intranet?
An Intranet must be designed for the enterprise's or organization's needs (at the level of the services to be implemented). The intranet must, therefore, not only be designed by the computer engineers of the enterprise but within the scope of a project which takes into account the needs of all the parties interacting with the company.
Insofar as the physical setup is concerned, it is sufficient to set up a web server (for example, a machine running under Linux with the Apache web server and the database server MySQL or rather a server under Windows with the web server Microsoft Internet Information Server). It is then sufficient to configure a domain name for the server (for exampleintranet.your_entreprise.com. Please note that there are CMS systems (content management systems) that allow the management of the publication of pages by a team of editors.
What is an extranet?
An extranet is an extension of the company's information system to its partners outside the network. Access to the extranet must be secured to the extent that the same provides access to the information system for persons outside the enterprise.
This might involve simple authentication (authentication via username and password) or strong authentication (authentication via a certificate). It is recommended to use HTTPS for all web pages consulted from the outside to secure the transport of HTTP queries and answers and to prevent, in particular, the open transfer of the password on the network.
An extranet is, therefore, neither an Intranet nor an Internet site. It is a supplementary system providing, for example, the clients of an enterprise, its partners, or its subsidiaries with privileged access to specific enterprise computer resources via a Web interface.