Intranet

One of the most desirable features of the Internet is the ability to access information from anywhere, independent of geographical location. However, there are valid reasons why a corporation may not want to grant worldwide access to its internal business information. This has led to Internet-like services restricted to inside a company that is referred to as an intranet. Intranets have been called a paradigm shift in internal business operations because of the potential networking efficiencies (dynamic online corporate information instantly accessible) and the standard, universal computer interface for all employees within an organization.

An intranet is an enterprise network (spanning geographical boundaries to connect different types of computers in various parts of an organization) that provides users with Internet application tools (i.e., web browsers) to access organizational information. Note that an intranet is an internal network to link organizational members to organizational information that is completely controlled by the organization. If any Internet connection does exist (one does not have to exist), a firewall prevents outside computers anywhere on the Internet from accessing computers on the intranet.

Intranets are popular for several reasons: (1) the infrastructure is often already in place in terms of computers, software, and connectivity for any networks with Internet access; (2) they work, allowing all organizational members instant and uniform access to broadcast organizational information, internal databases, and internal collaboration; (3) they scale well because the technology is the same as that used in the Internet; and (4) intranets are secure from the Internet. Due to the popularity of the World Wide Web, most intranets are implementations of an enterprise network providing access to web server(s).

In the web context, to create an intranet requires the following: (1) establishing a web server, requiring hardware and software; (2) establishing web server access by building a TCP/IP (Transmission Control Protocol/Internet Protocol) network—TCP/IP is the protocol suite that provides interoperability on the Internet; (3) loading client web browsers on each user's computer; and (4) creating a web homepage document using HTML (hypertext markup language) or an HTML editor. A big advantage of using an intranet is that most employees are already familiar with using the Internet and web so little extra training is needed.

Protection for an intranet connected to the Internet is provided by a fire-wall—a computer or group of computer systems that enforces an access control policy by blocking traffic or permitting traffic. Typically, a firewall is one computer that sits between the intranet and the Internet filtering packets according to various criteria. Firewalls simplify security management because network security can be consolidated on firewall systems rather than being distributed on systems all over an internal network. Firewalls thus offer a convenient point where logging and auditing functions can provide summaries about traffic flows passing through, traces of inbound and outbound connections, attempts to break through, and alarms for attacks as they occur. Without a firewall, protection defaults to individual computer security mechanisms implemented on each intranet computer device. Before implementing an intranet relying on a firewall, an organization must inventory all its traffic routing since a firewall cannot filter packets that are not routed through it.

A web-based intranet allows an organization to control information by tracking aggregate web traffic and individual user traffic. Emerging intranet products are developing methods to infer user information from web server request log information in files that can be used with relational databases for specific queries. Other products track web page users's access, the paths users follow through webpages, and the amount of e-mail an individual user sends and receives. It has already become common commercial practice for companies to keep track of search topics requested by an individual userand compile databases that allow tailored information designed for individual users.

Most companies today implement some form of intranet for internal operations. For example, KPMG, a management consulting firm, moved all of its information assets to an intranet called KWorld. The success of Cisco Systems has been largely attributed to its innovative corporate intranet. Even while selling systems using a non-interoperable proprietary protocol (Systems Network Architecture—SNA), IBM was also widely credited with having the largest TCP/IP corporate intranet. The People's Republic of China (PRC) is attempting to build a national intranet to take advantage of established Internet connectivity while limiting access to information forbidden by Chinese Internet regulations—if successfully implemented it would be the largest intranet in the world.

William Yurcik

Internet; Network Design; Networks; Telecommunications.

Comer, Douglas E. The Internet Book: Everything You Need to Know About Computer Networking and How the Internet Works. 3rd ed. Prentice Hall, 2000.