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Please, read the following text in order to answer questions 21 to 25.
Are scientists leaving the net?
The scientists who helped create the Internet may be leaving it for less crowded cyberspaces. Having been on the Internet longer than the rest of us, scientists use it differently.
Premier researchers use the Internet to test projects like real-time, 3D models of colliding galaxies or rampaging tornadoes. For tasks like that, the Internet is no longer fast enough or reliable enough. And some scientists are frustrated. For them, the information superhighway is full of bumper-to-bumper traffic.
Visionary engineers at the National Science Foundation, fortunately, have long foreseen such congestion. As an alternative, they created the very high-speed Backbone Network Service (VBNS). It links a handful of government and university labs at speed of 155,000,000 bits per second, or 10,000 times faster than a standard modem. By the year 2000, a new generation of equipment and another round of research could give scientists data pipes 12 times faster than that. Among other tricks, these new high bandwidth networks will allow scientists to manipulate huge computer files so unwieldy they are now shipped by four-wheeled means. “Never underestimate the bandwidth of a pick-up truck full of data”, jokes Daniel Sandin of the University of Illinois.
Sandin and his team in Chicago will use the VBNS to immerse goggled humans at different locations into the same type of jaw-dropping virtual reality simulation generated by a supercomputer. “You could not do that on the Internet,” says Thomas Defanti, Sandin’s colleague. “The Internet is so congested that for any kind of highbandwidth use, it is essentially rendered useless.”
“Simply adding lanes is not going to work,” adds Beth Gaston of the National Science Foundation. “Our role is to spur the technology forward” – Mark Uheling.
(Popular Science, September 1996, p.60)
The main purpose of the text is to: