技术经济评估互联网协议版本6ipv6讨论稿

1Introduction1 Over the past decade, the Internet has revolutionized computer andcommunications activities.First envisioned as a tool for facilitatinginteraction among government and academic researchers, the Internetnow touches almost every aspect of society.It has vastly expanded theindividual and societal benefits of personal computers by becoming theprimary mechanism for the dissemination, retrieval, and exchange ofinformation between and among millions of computer users worldwide. The social effects of these developments have been immense.TheInternet has enabled consumers to shop more conveniently, choose froma wider selection of products and vendors, and customize theirpurchases.As a result, according to one estimate, consumers spent$12.8 billion online in the first three months of 2003, up 27 percent fromthe same period in 2002.2Similarly, the growth of online distance learning classes and medical reference Web sites has given peoplegreater access to educational and medical resources.Governmentagencies and organizations can more easily process requests from andmake information available to citizens, thereby facilitating interactionbetween citizens and government and reducing the costs to governmentof providing essential services.3The Internet also creates opportunitiesfor individuals to participate or to participate more fully in the marketplaceof ideas that is the foundation of American democracy. The Internet’s effects on the economy have been equally profound. Litanand Rivlin assert that a major feature of the Internet revolution “is itspotential to make the whole economic system, nationally andinternationally, more competitive by rendering many markets closer toeconomists’ textbook model of perfect competition, characterized bylarge numbers of buyers and sellers bidding in a market with perfectinformation.”4Although the Internet has helped increase competitivepressures in many product and service markets, it has also equippedmany businesses to thrive in the new market environment.Internet-based electronic mail and business-to-business software applicationshave enabled companies to reduce transaction costs; increasemanagerial efficiency; and improve the ways in which they transmitbilling, inventory, and other information.That, in turn, has allowedcompanies to bring better products to the market more quickly and atlower cost. The United States has played a major role in the development of thenetworks, standards, and conventions that spawned the Internet, andAmericans have become major users of IP -based services.As a result,the United States has been and continues to be a major beneficiary ofthe Internet revolution.Americans’ extensive use of the Internet hascontributed to the robust performance of our economy over the lastdecade, both in absolute terms and relative to other nations.America’scentral role in the creation and operation of the Internet has also put U.S.companies at the cutting edge of information technology markets, whichhave been a primary engine of economic growth and job creationdomestically in recent years. For these and many other reasons, the United States has a substantial interest in the future evolution of theInternet and in ensuring that U.S. firms can continue to participate fully inthat evolution and its economic spillovers. 1.1THE INTERNET PROTOCOL AND IPV6 This paper focuses on one of the communications protocols5that lie atthe heart of the Internet — the Internet Protocol (IP), which enables dataand other traffic to traverse the Internet and to arrive at the desireddestination.IP not only provides a standardized “envelope” for theinformation sent, but it also contains “headers ” that provide addressing,routing, and message-handling information that enables a message to bedirected to its final destination over the various media that comprise theInternet. The current generation of IP, version 4 (IPv4), has been in use for morethan 20 years and has supported the Internet’s growth over the lastdecade.With the transformation of the Internet in the 1990s from aresearch network to a commercialized network, concerns were raisedabout the ability of IPv4 to accommodate emerging demand, especiallythe anticipated demand for unique Internet addresses.As a result, theInternet Engineering Task Force (IETF) began work on the nextgeneration IP, which became IP version 6 (IPv6).6 IPv6 offers a number of potential advantages over IPv4, most notably amassive increase in the number of Internet addresses.Demand for suchaddresses will increase as more and more of the world’s populationrequest Internet access.Cisco Systems notes that if the 15 largestcountries were to assign unique addresses to only 20 percent of theirpopulations, the resulting demand would easily exhaust the remaining supply of IPv4 addresses.7Continued growth in mobile telephone andmobile data terminals (such as personal data assistants [PDAs]) will alsoexpand demand for Internet addresses.The situation may become