The Internet began in the 1960s as a small network of academic and (1)___________________________________________.Originally limited to researchers at a handful of universities and government facilities,the Internet has quickly become a worldwide network providing users with information on a range of subjects and allowing them to purchase goods directly from companies via computer.By 1999,84 million U.S. citizens had access to the Internet at home or work.More and more Americans are paying bills, shopping, ordering airline tickets,and purchasing stocks via computer over the Internet.Internet banking is also becoming increasingly popular.At present, 14 percent of Internet households conduct their banking by means of the Internet,and the figure is expected to double during the next two or three years.(2)_________________________________________________.With a credit or debit card,an Internet user can order almost anything from an Internet site and have it delivered to their home or office.Companies doing business over the Internet need sophisticated security measures to protect credit card,bank account, and social security numbers from illegal access as they pass across the Internet.Any organization that connects its networks to the global Internet must carefully control the access point to ensure that outsiders cannot break into the organization's internal networks or (3)___________________________________________.