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1900 - 2000 A.D. |
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1904
First broadcast talk
1918
Invention of the short-wave radio
1929
Invention of television in Germany and Russia
1941
Invention of microwave transmission
1946
Long-distance coaxial cable systems and mobile telephone services are introduced in the USA.
1957
 Sputnik, the first satellite, is launched by the USSR
First data transmissions over regular phone circuits.
At the beginning of the story of today's global data networks is the story of the development of satellite communication.
In 1955 President Eisenhower announced the USA's intention to launch a satellite. But it in the end it was the Soviet Union, which launched the first satellite in 1957: Sputnik I. After Sputnik's launch it became evident that the Cold War was also a race for leadership in the application of state-of-the-art technology to defense. As the US Department of Defense encouraged the formation of high-tech companies, it laid the ground to Silicon Valley, the hot spot of the world's computer industry.
The same year as the USA launched their first satellite - Explorer I - data was transmitted over regular phone circuits for the first time, thus laying the ground for today's global data networks.
Today's satellites may record weather data, scan the planet with powerful cameras, offer global positioning and monitoring services, and relay high-speed data transmissions. Yet up to now, most satellites are designed for military purposes such as reconnaissance.
1969
ARPAnet online
ARPAnet was the small network of individual computers connected by leased lines that marked the beginning of today's global data networks. An experimental network it mainly served the purpose of testing the feasibility of wide area networks and the possibility of remote computing. It was created for resource sharing between research institutions and not for messaging services like E-mail. Although US military sponsored its research, ARPAnet was not designed for directly martial use but to support military-related research.
In 1969 ARPANET went online and linked the first two computers, one located at the University of California, Los Angeles, the other at the Stanford Research Institute.
Yet ARPAnet did not become widely accepted before it was demonstrated in action to a public of computer experts at the First International Conference on Computers and Communication in Washington, D. C. in 1972.
Before it was decommissioned in 1990, NSFnet, a network of scientific and academic computers funded by the National Science Foundation, and a separate new military network went online in 1986. In 1988 the first private Internet service providers started offering access to NSFnet to a general public. After having become the backbone of the Internet in the USA, in 1995 NSFnet was turned into a consortium of commercial backbone providers. This and the launch of the World Wide Web added to the success of the global data network we call the Net.
In the USA it was already in 1994 that commercial users outnumbered military and academic users.
Despite the rapid growth of the Net, most computers linked to it are still located in the United States.
1971
Invention of E-Mail
1979
Introduction of fiber-optic cable systems
1992
Launch of the World Wide Web
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Satellites
Communications satellites are relay stations for radio signals and provide reliable and distance-independent high-speed connections even at remote locations without high-bandwidth infrastructure.
On point-to-point transmission, the transmission method originally employed on, satellites face increasing competition from fiber optic cables, so point-to-multipoint transmission increasingly becomes the ruling satellite technology. Point-to-multipoint transmission enables the quick implementation of private networks consisting of  very small aperture terminals (VSAT). Such networks are independent and make mobile access possible.
In the future, satellites will become stronger, cheaper and their orbits will be lower; their services might become as common as satellite TV is today.
For more information about satellites, see How Satellites Work (http://octopus.gma.org/surfing/satellites) and the Tech Museum's satellite site (http://www.thetech.org/hyper/satellite).
 http://www.whatis.com/vsat.htm
http://octopus.gma.org/surfing/satellites
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