The Net connections can be based on wire-line and wireless access technolgies.
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Usually several kinds of network connections are employed at once. Generally speaking, when an E-mail message is sent it travels from the user's computer via copper wires or coaxial cables
Satellite communication
Although facing competition from fiber-optic cables as cost-effective solutions for broadband data transmission services, the space industry is gaining increasing importance in global communications. As computing, telephony, and audiovisual technologies converge, new wireless technologies are rapidly deployed occupying an increasing market share and accelerating the construction of high-speed networks.
Privatization of satellite communication
Until recently transnational satellite communication was provided exclusively by intergovernmental organizations as
Scheduled privatization of intergovernmental satellite consortia:
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When Intelsat began to accumulate losses because of management failures and the increasing market share of fiber-optic cables, this organizational scheme came under attack. Lead by the USA, the Western industrialized countries successfully pressed for the privatization of all satellite consortia they are members of and for competition by private carriers.
As of February 2000, there are 2680 satellites in service. Within the next four years a few hundred will be added by the new private satellite systems. Most of these systems will be so-called Low Earth Orbit satellite systems, which are capable of providing global mobile data services on a high-speed level at low cost.
Because of such technological improvements and increasing competition, experts expect satellite-based broadband communication to be as common, cheap, and ubiquitous as satellite TV today within the next five or ten years.
Major satellite communication projects
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Source: Analysys Satellite Communications Database
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Until the 19th century "early computers", probably better described as calculating machines, were basically mechanical devices and operated by hand. Early
Therefore
After working on the Difference Engine for ten years Babbage was inspired to build another machine, which he called Analytical Engine. Its invention was a major step towards the design of modern computers, as it was conceived the first general-purpose computer. Instrumental to the machine's design was his assistant, Augusta Ada King, Countess of Lovelace, the first female computer programmer.
The second major breakthrough in the design of computing machines in the 19th century may be attributed to the American inventor Herman Hollerith. He was concerned with finding a faster way to compute the U.S. census, which in 1880 had taken nearly seven years. Therefore Hollerith invented a method, which used cards to store data information which he fed into a machine that compiled the results automatically. The punch cards not only served as a storage method and helped reduce computational errors, but furthermore significantly increased speed.
Of extraordinary importance for the evolution of digital computers and
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The Internet can be used in in different ways: for distributing and retrieving information, for one-to-one, one-to-many and many-to-many communication, and for the access services. Accordingly, there are different services on offer. The most important of these are listed below.
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A CPU is the principal part of any digital computer system, generally composed of the main memory, control unit, and arithmetic-logic unit. It constitutes the physical heart of the entire computer system; to it is linked various peripheral equipment, including input/output devices and auxiliary storage units...
Built by Remington Rand in 1951 the UNIVAC I (Universal Automatic Computer) was one of the first commercially available computers to take advantage of the development of the
The first half of the 20th century was the era of the vacuum tube in electronics. This variety of electron tube permitted the development of radio broadcasting, long-distance
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
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 (
Microwave transmission systems based on terrestrial antennas are similar to satellite transmission system. Providing reliable high-speed access, they are used for cellular phone networks.
The implementation of the
Internet exchanges are intersecting points between major networks.
List of the World's Public Internet exchanges (
In mathematics, the term binary number system refers to a positional numeral system employing 2 as the base and requiring only two different symbols, 0 and 1. The importance of the binary system to information theory and computer technology derives mainly from the compact and reliable manner in which data can be represented in electromechanical devices with two states--such as "on-off," "open-closed," or "go-no go."
Initially computer programmers had to write instructions in machine language. This
DSL connections are high-speed data connections over copper wire telephone lines. As with cable connections, with DSL you can look up information on the Internet and make a phone call at the same time but you do not need to have a new or additional cable or line installed. One of the most prominent DSL services is ISDN (integrated services digital network, for more information click here (
b. Nov. 2, 1815, Lincoln, Lincolnshire, England
d. Dec. 8, 1864, Ballintemple, County Cork, Ireland
English mathematician who helped establish modern symbolic logic and whose algebra of logic, now called Boolean algebra, is basic to the design of digital computer circuits. One of the first Englishmen to write on logic, Boole pointed out the analogy between the algebraic symbols and those that can represent logical forms and syllogisms, showing how the symbols of quantity can be separated from those of operation. With Boole in 1847 and 1854 began the algebra of logic, or what is now called Boolean algebra. It is basically two-valued in that it involves a subdivision of objects into separate classes, each with a given property. Different classes can then be treated as to the presence or absence of the same property.