ABSTRACT
The Internet, arguably one of the most successful global infrastructures, began its life humbly enough as just two ARPANET nodes-one at Leonard Kleinrock’s Network Measurement Center at UCLA* and the other at Doug Engelbart’s group at SRI.† In late 1969, the first host-to-host message was sent from UCLA to SRI heralding the birth of the infrastructure that would help usher the human race into information age [Leiner et al. 1997]. From a handful of users in late 1969, the usage of the Internet within the United States grew nearly a million-fold over two decades to about 2 million users‡ in 1990 [World Bank 2011c]. With the advent of the World Wide Web around 1990, the Internet usage has seen a staggering rise. Figure 7.1 shows the growth in Internet usage within the United States since 1990. The worldwide statistics of Internet usage are also impressive. As of December 31, 2011, the world had about 7 billion people,§ and about 2.2 billion Internet users¶ [Internet Stats 2011]. More than three out of every four people in the United States and two out of every seven people in the world use the Internet today. The growth of the World Wide Web is just as impressive. In 2008, it was estimated that there were about a trillion different resources (URLs) on the web, or more than 140 resources for every person on the planet [Alpert and Hajaj 2008].
