|
Late 1960s - Early 1970s: Third Generation Computers |
|
One of the most important advances in the development of computer hardware in the late 1960s and early 1970s was the invention of the integrated circuit, a solid-state device containing hundreds of transistors, diodes, and resistors on a tiny silicon chip. It made possible the production of large-scale computers (mainframes) of higher operating speeds, capacity, and reliability at significantly lower costs.
Another type of computer developed at the time was the minicomputer. It profited from the progresses in microelectronics and was considerably smaller than the standard mainframe, but, for instance, powerful enough to control the instruments of an entire scientific laboratory. Furthermore operating systems, that allowed machines to run many different programs at once with a central program that monitored and coordinated the computer's memory, attained widespread use.
|
|
|
|
Fiber-optic cable networks
Fiber-optic cable networks may become the dominant method for high-speed Internet connections. Since the first fiber-optic cable was laid across the Atlantic in 1988, the demand for faster Internet connections is growing, fuelled by the growing network traffic, partly due to increasing implementation of corporate networks spanning the globe and to the use of graphics-heavy contents on the World Wide Web.
Fiber-optic cables have not much more in common with copper wires than the capacity to transmit information. As copper wires, they can be terrestrial and submarine connections, but they allow much higher transmission rates. Copper wires allow 32 telephone calls at the same time, but fiber-optic cable can carry 40,000 calls at the same time. A capacity, Alexander Graham Bell might have not envisioned when he transmitted the first words - "Mr. Watson, come here. I want you" - over a copper wire.
Copper wires will not come out of use in the foreseeable future because of technologies as DSL that speed up access drastically. But with the technology to transmit signals at more than one wavelength on fiber-optic cables, there bandwidth is increasing, too.
For technical information from the Encyclopaedia Britannica on telecommunication cables, click here. For technical information from the Encyclopaedia Britannica focusing on fiber-optic cables, click here.
An entertaining report of the laying of the FLAG submarine cable, up to now the longest fiber-optic cable on earth, including detailed background information on the cable industry and its history, Neal Stephenson has written for Wired: Mother Earth Mother Board. Click here for reading.
Susan Dumett has written a short history of undersea cables for Pretext magazine, Evolution of a Wired World. Click here for reading.
A timeline history of submarine cables and a detailed list of seemingly all submarine cables of the world, operational, planned and out of service, can be found on the Web site of the International Cable Protection Committee.
For maps of fiber-optic cable networks see the website of Kessler Marketing Intelligence, Inc.
http://www.britannica.com/bcom/eb/article/4/0...
http://www.britannica.com/bcom/eb/article/4/0...
http://www.wired.com/wired/archive/4.12/ffgla...
http://www.pretext.com/mar98/features/story3....
|
|
|