The Evolution of the Internet

The world's largest network of computer networks got its original name from the U.S. military arm that funded it: Arpanet was for the Advanced Research Projects Agency. Back in 1969 when Arpanet was created, it connected five sites: UCLA, Stanford, UC Santa Barbara, the University of Utah and BBN. In 1983, the U.S. Defense Department spun-off MILNET*, which was the part of Arpanet that carried unclassified military communications. Arpanet was renamed the Internet in 1984, when it linked 1,000 hosts at university and corporate labs.

*MILNET was later re-named the Defense Data Network and finally NIPRNET, for Non-classified IP Router Network.

The number of computers connected to the Internet has grown dramatically from the network's humble beginnings, when it connected four computers at university research labs. Today, the Internet links more than 440 million computers directly, and millions more have Internet access through private addressing schemes.

Internet usage has exploded since 1995, when researchers first started tracking this statistic. Although estimates vary from the Internet having 1 billion to 1.5 billion users, everyone agrees that the 'Net has room for growth as the worldwide population tops 6 billion. That leaves more than 4 billion people around the world without Internet access today.

The Internet has changed from a U.S.-dominated communications medium to one that is seeing its fastest growth in Asia and Europe. Here's how the Internet's geographic reach stacked up then and now.

The Internet's Domain Name System was created in 1984 to match complex IP addresses with easy-to-remember names ending in extensions such as .com, .org, .edu, .gov, .mil and country codes including .de for Germany. In 1998, the U.S. Department of Commerce privatized domain name registrations and operations through the creation of the Internet Corporation for Assigned Names and Numbers. Since then, domain name sales have risen nearly 10-fold, but .com remains the most popular domain.

In 1990, Tim Berners-Lee invented the World Wide Web as a method of publishing information in a hypertext format on the Internet. The Web began to take off in 1993, after computer science student Marc Andreessen created the first popular Web browser, known as Mosaic. Since then the number of Web sites and Web pages has exploded.

Experts quibble about how much traffic is on the Internet and how fast it's growing. Is it growing at 50% to 60% a year? Or 100% a year? But there's no question that the figure has exploded since 1974, when daily traffic on the Internet surpassed 3 million packets. First measured in terabytes and petabytes, scientists say the future points to monthly traffic volumes in the exabytes - which is 10 to the 18th power bytes. Whatever you call it, that's a lot of packets!

E-commerce burst on the scene in the mid-1990s, and it's been growing ever since - both in total sales and as a percentage of all retail sales. Worldwide e-commerce statistics are hard to find, but the U.S. Commerce Department has been tracking U.S. e-commerce sales since the fourth quarter of 1999. Here's a snapshot of their findings:

Back in 1988, the Morris Worm was the first major attack on the Internet, disabling 10% of the Internet's 60,000 host computers. Today, hundreds of more sinister attacks are aimed at Internet users each day. Indeed, the U.S. Computer Emergency Readiness Team (US-CERT) stopped counting the number of security incident reports it received in 2004 because attacks against Internet-connected systems had become so commonplace that it felt this figure was getting too big to track.

Back in 2003, an estimated 15 billion spam messages were sent over the Internet daily. That means 45% of all e-mail messages were unsolicited pitches for things such as drugs and penny stocks. Those figures seem quaint today, compared to the 164 billion spam messages being sent daily, representing 97% of all e-mail. During the last five years, spam has changed from being annoying to being malicious, with the growth of spam-driven phishing scams.

Experts say the Internet will continue along its phenomenal growth path, despite the current global economic crisis. What's different is that the Internet will become increasingly mobile and social. By 2012, more people will access the Internet via cell phones than PCs. Their favorite activities will be downloading music, videos and ringtones rather than searching the Web or sending e-mail.