History Of The Internet
The Internet grew out of many developments in computer networking and telecommunications research. DARPAnet was an early (1960's) computer network research project of the U.S. military. The idea was to develop a model for inviolable communications networks; in the event of nuclear attack taking out a major American city, the communications network for the country would still survive. Tandem developments in both local and wide area network research continued throughout the 1970's and 1980's. In the mid 1980's the National Science Foundation established the NSFnet which linked a high speed national backbone network to five super computing centers which were located in academic, military and research institutions around the country. Seven regional "midlevel provider networks" linked campus networks to the backbone thus providing a national network that allowed researchers at institutions all over the country to communicate with each other and collaborate on projects. The original purpose of this publicly funded network was to support education and research, consequently all commercial uses were banned and only people in government, the military and academia had access to the network.
In 1991, the NSF gradually started backing off from its subsidy of the backbone network. Among its first actions in this respect was to allow commercial access to the Internet. The CIX, commercial information exchange, was born, and new midlevel networks offering access for businesses to the national backbone network began to appear. With commercial access to the Internet, businesses and all kinds of agencies began to use the Internet to communicate, exchange data and distribute information; a host of businesses called Internet Service Providers (ISPs) sprang up. ISPs provide dialup access to the Internet; an individual or a business opens an account with the ISP, dials into the ISP's computer and via the ISP's computer connects to the Internet.
ISPs are different from the commercial online services such as Prodigy, CompuServe, America Online and Microsoft Network. The commercial online vendors offer an array of services such as e-mail, discussion groups, "information arcades", and now gateway access to the Internet. The commercial services pull together access to popular resources, some available on the Internet, and some maintained on the vendors' computers, in easy-to-navigate menus and directories. An ISP simply offers direct connection to the Internet, the user determines the resources s/he connects to. An analogy of the difference between the commercial services and the ISPs could be the difference between shopping at a mall and shopping at indvidual stores located all over a city. At the mall (the analog for the commercial online service), several stores have been pulled together in one sort of unified looking building. Each store (information source) retains its individuality, but the shopper simply arrives at the mall and moves from store to store (information source to information source). Shopping at individual stores (accessing the Internet via an ISP) allows a user more choice in where he shops, but getting to the store (information resource) requires more knowledge, for instance, the store's address and what kind of store it is.
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