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The Internet, the Intranet, and Networks

We live in a rapidly changing information society – that is, a society in which large groups of employees generate or depend on information to perform their jobs. The need for more and better information will only continue to grow.

The Internet is a worldwide network of computers linked through telecommunications. The Internet has profoundly altered the way people communicate, learn, do business, and find entertainment. Although many people believe the Internet began in the early 1990s, its origins can actually be traced to the late 1950s. Over the past four decades, the network evolved from a system for government and university researches into a tool used by millions around the globe for communication, information, entertainment, and e-business. Clearly, the Internet is here to stay.

Enabling users around the world to communicate with each other electronically, the Internet provides access to a huge array of information sources. The Internet’s most commonly used network for finding information is the World Wide Web. The World Wide Web (or more simply, the Web) is collection of interconnected Web sites or “pages’ of text, graphics, audio and video within the Internet. To get on the Internet, you need a computer, a modem, and an Internet service provider (ISP), such as AT&T, America Online, Verizon, or other companies that provide a connection to the Web. Internet service providers (ISPs) provide customers with a connection to the Internet through various phone plugs and cables. Today, connections to the Internet include simple telephone lines or faster digital subscriber lines (DSLs) and cable broadband that carry larger amounts of data at quicker transfer speeds. Broadband technology is a general term referring to higher speed Internet connections that deliver data, voice, and video material. And with new wireless technology, it is possible to access the Internet by using your laptop computer, cellular phone, and other wireless communications devices.

The most popular wireless network currently is Wi-Fi. Wi-Fi – short for wireless fidelity – is a wireless network that connects various devices and allows them to communicate with one another through radio waves. Wi-Fi allows high-speed wireless Internet connections when linked to a specially equipped modem. Wireless fidelity (Wi-Fi) networks are changing the way individuals and businesses use the Internet. In the not-too-distant future, experts expect Wi-Fi to link all sorts of devices – not just computers, but lamps, stereos, appliances, and more – and to fully integrate the Internet into our lives. Wi-Fi is also transforming how companies use the Internet. Some firms use Wi-Fi to replace expensive wired networks or to maintain communications even in hard-to-reach places like warehouses. As such, investments in Wi-Fi can boost productivity and improve the ease and connectivity of multiple devices. Bluetooth technology allows mobile phones, computers, and personal digital assistants (PDAs), as well as other devices, to be interconnected using a short-range wireless connection .Using this technology, users can have all mobile and fixed computer devices in sync with one another. Bluetooth wireless technology is installed on more than 5 million units every week as well as some automobiles, such as select BMWs.

Internet Voice, also known as Voice over Internet Protocol (VoIP), allows you to make telephone calls using broadband Internet connections instead of traditional hard-wired, land lines. While some services only work through your computer, others allow you to use your traditional phone line with an adapter. Companies operating in this market include Vonage, Skype, Sunrocket, Time Warner Cable, and Net Zero, to name a few.

An intranet is a smaller version of the Internet for use within a firm. Using a series of customized Web pages, employees can quickly find information about their firm as well as connect to external sources. Intranets are similar to extranets, but they limit access only to employees or other authorized users. An intranet blocks outsiders without valid passwords from entering its network by incorporating software known as firewall. Firewalls are available as off-the-shelf packages such as Firewall/Plus and On Guard. They limit data transfers to certain locations and log system use so managers can identify attempts to log on with invalid passwords and other threats to system security. Generally, intranet sites are protected, and users must supply both a user name and a password to gain access to a company’s intranet site. Some businesses open up their intranets to other selected individuals and companies through an extranet, a network of computers that permits selected companies and other organizations to access the same information and may allow different managers in various organizations to collaborate and communicate about the information. For example, one of the most common uses of an extranet is for a company such as Wal-Mart to permit suppliers such as Procter & Gamble or Kraft to access the Wal-Mart MIS to determine inventory levels and product availability. An extranet allows users to share data, process orders, and manage information.

Both the Internet and intranets are examples of a computer network. A computer network is a group of two or more computers linked together that allows users to share data and information. Today, two basic types of networks affect the way employees and the general public obtain data and information. A wide-area network (WAN) is a network that connects computers over a large

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geographic area, such as a city, a state, or even the world. The world’s most popular WAN is the Internet. In addition to the Internet, other WANs include private corporate networks and research networks. A local-area network (LAN) is a network that connects computers that are in close proximity to each other, such as an office building or a college campus. LANs allow users to share files, printers, games, or other applications. Typically, LANs also will allow users to connect to the Internet.

To maintain their competitive edge, companies want to be able to share larger chunks of information among employees and partners faster than ever before. To do so, they have turned to broadband technology – digital, fiber-optic and wireless network technologies that compress data and transmit them at blinding speeds. Table below shows the different types of broadband technologies currently available. The growth in broadband, especially among individual computer users, has been slower than expected, partly due to cost. However, most observers still consider broadband to be the future of the Internet.

TYPES OF BROADBAND TECHNOLOGIES

Technology	Transmission Method
Digital Subscriber Lines (DSL)	Standard copper-wire phone lines
Cable modems	Coaxial cable (as used in cable television)
Fiber-optic network	Optical cables
Wireless network	Microwave or satellite transmission
Integrated Services Digital Network (ISDN)	Standard copper-wire phone lines and other media
T1 and T3 lines	Special dedicated phone connections

Optical networks are one of the newest broadband technologies. They convert information into tiny bits of light that are transmitted over fiber-optic cables made of glass. Long-distance phone carries are in the process of rapidly installing optical networks to increase the number of transmissions and the speed at which they travel. Optical networks have a million times the capacity of traditional phone networks because light particles are lighter than electrical impulses, they can be separated into different colors to create separate channels, and glass allows more rapid travel than copper.