Chapter 42. How Intranets Work

Businesses increasingly use Internet technology to create private corporate networks called intranets. These intranets are used for a wide variety of purposes, such as email, group brainstorming, group scheduling, access to corporate databases and documents, videoconferencing, and the buying and selling of goods and services.

Intranets use TCP/IP networks and technologies as well as Internet resources such as the World Wide Web, email, Telnet, and FTP. However, the network and its resources are used privately by businesses and are not available to people outside the company. An intranet is separated from the rest of the Internet by a firewalla hardware and software combination that prohibits unauthorized access to the intranet. People who work in the company can access the Internet and use its resources, but firewalls keep out intruders. Turn to Chapter 44, "How Firewalls Work," to learn more about firewalls.

Intranets use a combination of off-the-shelf software, such as web browsers, and customized software, such as database querying tools. Because intranets are based on Internet standard protocols, it will always be possible to quickly update them with the latest in network technologies.

In the long term, companies will make the most use of intranets in workgroup applicationssoftware that enables people to work cooperatively with their computers. Many kinds of workgroup software exist. These programs enable people to participate in discussions and videoconferencing across the country and across the world, share databases, track documents, and much more.

The key to workgroup software is that it enables people to go beyond simply communicating and lets them work together on shared documents.

One of the most basic pieces of workgroup software is messaging softwareprograms that enable people to publicly participate in group discussions.

What makes intranet messaging software especially useful is the way it integrates with other Internet and intranet technologies. For example, some discussion software allows the use of Hypertext Markup Language (HTML) embedded inside messages. This means that from within a discussion, someone could embed a link to a web page or other intranet resource.

A more sophisticated workgroup application is desktop videoconferencing. This application requires that everyone involved have computer-linked video cameras as well as hardware and software that enable computers to send and receive voice and sound. While sitting at computers, people can see and speak to one another.

A related technology is called whiteboard software. Whiteboard software lets people see what is on someone else's computer on an intranet while sitting at their own computers. This means people on the same intranetwhether they're on opposite sides of the country from one anothercan easily comment on one another's work.

Increasingly popular among businesses are Virtual Private Networks (VPNs), which let employees connect securely to the company intranet no matter where they areat home, on the road, or anywhere else. They use a kind of "tunneling" technology to let people use the public Internet to connect to the company intranet, while keeping all communications secure and encrypted.