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Basics: Limitations |
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Temporal
Copyright protection is limited in time. Many countries have adopted a term of protection that starts at the time of the creation of the work and ends 50 years (in some cases 70 years) after the death of the author. Under some national laws exist exceptions either for certain kinds of creations or for certain uses. After the protection has expired works pass into the public domain. In recent years a tendency towards the lengthening of the term of protection has emerged.
Geographic
The owner of a copyrighted work is protected against acts restricted by copyright under the law of a certain country. To gain protection against such acts in other countries he must refer to the respective national legislation. If both countries are members of one of the international conventions on copyright, the practical problems arising from this geographical limitation are eased.
Non-Material Works
In some countries works that are not fixed in some material form are excluded from copyright protection. Also under certain national legislations, the texts of laws and decisions of courts and administrative bodies cannot be copyrighted (which is possible in several countries; then the government is the owner of the copyright in such works and can exercise his rights in accordance with the public interest).
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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....
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