Студопедия

КАТЕГОРИИ:

АстрономияБиологияГеографияДругие языкиДругоеИнформатикаИсторияКультураЛитератураЛогикаМатематикаМедицинаМеханикаОбразованиеОхрана трудаПедагогикаПолитикаПравоПсихологияРиторикаСоциологияСпортСтроительствоТехнологияФизикаФилософияФинансыХимияЧерчениеЭкологияЭкономикаЭлектроника


Text Eight




HOW THE INTERNET BECAME A BIG BOY*

In the summer of 1968, experts at the RAND Corporation, America's foremost Cold War think tank, were considering a strange strategic problem. How could the US authorities successfully communicate after a nuclear war? No matter how thoroughly a network was armoured or protected, its switches and wiring would always be vulnerable to bombs. An attack could reduce any conceivable network to tatters.

And how would the network itself be commanded and controlled? Any central authority would be an obvious and immediate target for an enemy missile. RAND mulled over this grim puzzle in deep military secrecy, and arrived at a daring solution. In the first place, they would design a network with no central authority. Furthermore, they would design it to operate while in tatters.

The principles were simple. All the nodes in the network would be equal in status, each with its own authority to originate, pass and receive messages. The messages themselves would be divided into packets. Each packet would begin at some specified source node, and end at some other specified destination node. It would wind its way through the network on an individual basis.

The route that the packet took would be unimportant. Only reaching its final destination would count. Basically, the packet would be tossed like a hot potato from node to node to node, until it ended up in the proper place. If big pieces of the network had been blown away, that simply wouldn't matter.

This excited and intrigued many, because it did sound like a theory for an indestructible network. In the autumn of 1969, the first node was installed in UCLA. By December 1969, there were four nodes on the infant network, which was named ARPANET, after its Pentagon sponsor (the Advanced Research Projects Agency). An added bonus was that scientists and researchers could share one another's computer facilities from a great distance away. This was a very handy service, for computer time was precious in the early 70s. In 1971 there were fifteen nodes in ARPANET; by 1972, thirty-seven nodes. And it was good.

By the second year of operation, however, an odd fact became clear. ARPANET'S users had warped the computer-sharing network into a dedicated, high-speed, federally subsidised electronic postal service. The main traffic was not long-distance computing, but news and personal messages.

The invention of the mailing list followed naturally. This was an ARPANET broadcasting technique in which an identical message could be sent automatically to large numbers of network subscribers. Interestingly, one of the first really big mailing lists was "SF-LOVERS," for science fiction fans. Discussing science fiction on the network was not work-related and was frowned upon by many ARPANET computer administrators, but this didn't stop it from happening.

The ARPA's original software for communication was known as NCP, 'Network Control Protocol', but as time passed and the technique advanced, NCP was superceded by a higher-level, more sophisticated standard known as TCP/IP. This software converted messages into streams of packets at the source, then reassembled them back into messages at the destination.

As early as 1977, TCP/IP was being used by other networks to link to ARPANET. ARPANET itself remained fairly tightly controlled, at least until 1983, when its military segment broke off and became MTLNET. But TCP/IP linked everyone to everyone else. And ARPANET itself, though it was growing, became a smaller and smaller neighbourhood amid the vastly growing constellation of other linked machines.

As the '70s and '80s advanced, other entire networks fell into the digital embrace of this ever-growing web of computers. Since TCP/IP was public domain, and the basic technology was decentralised and rather anarchic by its very nature, it was difficult to stop people from barging in and linking up. In fact, nobody really wanted to stop them from joining this branching complex of networks, which came to be known as 'the Internet'.

In 1984 the National Science Foundation got into the act. The new NSFNET set a blistering pace for technical advancement, linking newer, faster, shinier supercomputers, through thicker, faster links, upgraded and expanded, again and again, in 1986, 1988 and 1990. And other government agencies leapt in: NASA, the National Institutes of Health, the Department of Energy, each of them maintaining their own digital kingdom in the Internet confederation. A mere twenty years had passed since the invention of the ARPANET, but few people remembered it now.

For it had become a happy victim of its own overwhelming success. Its users scarcely noticed, for ARPANET'S functions not only continued but steadily improved. The use of TCP/IP standards for computer networking is now global. In 1971, there were only a handful of nodes in the ARPANET network. Today there are hundreds of thousands of nodes, scattered over virtually every country in the world. Five hundred million people use this gigantic mother of all computer networks.

The Internet's pace of growth in the early 1990s was spectacularly ferocious, at some point achieving a monthly growth of 20%. The number of 'host' machines with direct connection to TCP/IP doubled every year from 1988 to 1997. The Internet moved out of its original base in military and research institutions, into elementary and high schools, as well as into public libraries and the commercial sector and, of course, into millions of homes.

Why did so many people want to be on the Internet? One of the main reasons was simply freedom. The Internet is a rare example of the truly, modern, functional anarchy. There is no 'Internet Inc.' There are no official censors, no bosses, no board of directors, no stockholders. This virtual freedom, many hold, was the major reason why this form of communication attracted so many users so quickly.

And so the story goes. The real Internet of the future may bear very little resemblance to today's, or even today's predictions. Predictions have never seemed to have much to do with the seething, fungal development of the Internet. After all, today's Internet bears little resemblance to those original grim plans for RAND's post-holocaust command grid. It's a fine and happy irony. ( 5 100)


 


Поделиться:

Дата добавления: 2015-07-26; просмотров: 341; Мы поможем в написании вашей работы!; Нарушение авторских прав





lektsii.com - Лекции.Ком - 2014-2024 год. (0.006 сек.) Все материалы представленные на сайте исключительно с целью ознакомления читателями и не преследуют коммерческих целей или нарушение авторских прав
Главная страница Случайная страница Контакты