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Internet access connects individual computer terminals, computers, mobile devices, and computer networks to the Internet, enabling users to access Internet services, such as email and the World Wide Web. Internet service providers (ISPs) offer Internet access through various technologies that offer a wide range of data signaling rates (speeds). Consumer use of the Internet first became popular through dial-up Internet access in the 1990s. By the first decade of the 21st century, many consumers in developed nations used faster, broadband Internet access technologies. , broadband was ubiquitous around the world, with a global average connection speed exceeding 4 Mbit/s. ==History== The Internet developed from the ARPANET, which was funded by the US government to support projects within the government and at universities and research laboratories in the US – but grew over time to include most of the world's large universities and the research arms of many technology companies.〔Réseaux IP Européens (RIPE)〕〔(【引用サイトリンク】 work=16th APAN Meetings/Advanced Network Conference in Busan )〕 Use by a wider audience only came in 1995 when restrictions on the use of the Internet to carry commercial traffic were lifted.〔("Retiring the NSFNET Backbone Service: Chronicling the End of an Era" ), Susan R. Harris and Elise Gerich, ''ConneXions'', Vol. 10, No. 4, April 1996〕 In the early to mid-1980s, most Internet access was from personal computers and workstations directly connected to local area networks or from dial-up connections using modems and analog telephone lines. LANs typically operated at 10 Mbit/s and grew to support 100 and 1000 Mbit/s, while modem data-rates grew from 1200 and 2400 bit/s in the 1980s, to 28 and 56 kbit/s by the mid to late 1990s. Initially dial-up connections were made from terminals or computers running terminal emulation software to terminal servers on LANs. These dial-up connections did not support end-to-end use of the Internet protocols and only provided terminal to host connections. The introduction of network access servers (NASs) supporting the Serial Line Internet Protocol (SLIP) and later the point-to-point protocol (PPP) extended the Internet protocols and made the full range of Internet services available to dial-up users, subject only to limitations imposed by the lower data rates available using dial-up. Broadband Internet access, often shortened to just broadband and also known as high-speed Internet access, are services that provide bit-rates considerably higher than that available using a 56 kbit/s modem. In the US National Broadband Plan of 2009, the U.S. Federal Communications Commission (FCC) defined broadband access as "Internet access that is always on and faster than the traditional dial-up access", although the FCC has defined it differently through the years. The term broadband was originally a reference to multi-frequency communication, as opposed to narrowband or baseband. Broadband is now a marketing term that telephone, cable, and other companies use to sell their more expensive higher-data-rate products. Broadband connections are typically made using a computer's built in Ethernet networking capabilities, or by using a NIC expansion card. Most broadband services provide a continuous "always on" connection; there is no dial-in process required, and it does not “hog” phone lines.〔 Broadband provides improved access to Internet services such as: * Faster world wide web browsing * Faster downloading of documents, photographs, videos, and other large files * Telephony, radio, television, and videoconferencing * Virtual private networks and remote system administration * Online gaming, especially massively multiplayer online role-playing games which are interaction-intensive In the 1990s, the National Information Infrastructure initiative in the U.S. made broadband Internet access a public policy issue. In 2000, most Internet access to homes was provided using dial-up, while many businesses and schools were using broadband connections. In 2000 there were just under 150 million dial-up subscriptions in the 34 OECD countries〔The 34 OECD countries are: Australia, Austria, Belgium, Canada, Chile, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Japan, Korea, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Poland, Portugal, the Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States. (OECD members ), accessed 31 April 2012〕 and fewer than 20 million broadband subscriptions. By 2004, broadband had grown and dial-up had declined so that the number of subscriptions were roughly equal at 130 million each. In 2010, in the OECD countries, over 90% of the Internet access subscriptions used broadband, broadband had grown to more than 300 million subscriptions, and dial-up subscriptions had declined to fewer than 30 million.〔(''The Future of the Internet Economy: A Statistical Profile'' ), Organization for Economic Co-Operation and Development (OECD), June 2011〕 The broadband technologies in widest use are ADSL and cable Internet access. Newer technologies include VDSL and optical fibre extended closer to the subscriber in both telephone and cable plants. Fibre-optic communication, while only recently being used in premises and to the curb schemes, has played a crucial role in enabling broadband Internet access by making transmission of information at very high data rates over longer distances much more cost-effective than copper wire technology. In areas not served by ADSL or cable, some community organizations and local governments are installing Wi-Fi networks. Wireless and satellite Internet are often used in rural, undeveloped, or other hard to serve areas where wired Internet is not readily available. Newer technologies being deployed for fixed (stationary) and mobile broadband access include WiMAX, LTE, and fixed wireless, e.g., Motorola Canopy. Starting in roughly 2006, mobile broadband access is increasingly available at the consumer level using "3G" and "4G" technologies such as HSPA, EV-DO, HSPA+, and LTE. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Internet access」の詳細全文を読む スポンサード リンク
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