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A family plans a ski vacation in Utah, and their 10-year-old daughter browses the World Wide Web (WWW or Web) to find an inexpensive package tour. A college student plugs into the Internet jack in his residence hall room to communicate daily with friends and family via electronic mail (email). A health professions student subscribes to an electronic mail list and gains instant access to a lively dialog among her future colleagues on hot topics in their field. A man, worried about a tick bite a friend got on a Sunday hike, connects to the Centers for Disease Control in Atlanta to read the latest information about Lyme disease and to download color images of its characteristic skin rash. These are just a few examples that I know of the amazing ways the Internet and the WWW have changed our way of life. The Internet originated in December 1969 as a primitive link-up of 4 computers located at the Los Angeles and Santa Barbara campuses of the University of California, the Stanford Research Institute, and the University of Utah. It is doubtful that anyone then could have imagined just how fast their tiny computer network would grow. At the time of this writing, approximately 1/4 million registered local computer networks comprise more than 15 million host computers that serve more than 50 million users worldwide. These local networks are in turn joined into a single, vast, unified network, spanning more than 170 countries and linking computers of all different sizes, types, and operating systems with people who speak many different languages. One commonality among all these computers is their use of the same procedures for transmitting and receiving information over the net. These standards are embodied in the Internet Protocol (IP), which determines the conventions for addressing and routing information, and the Transmission Control Protocol (TCP), which governs how electronic messages are broken up into uniform-sized "packets" of data for transmission across the network and subsequent reassem |
