|
Acessing the Internet The Net connections can be based on wire-line and wireless access technolgies.
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:
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
Source: Analysys Satellite Communications Database | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
How the Internet works On the Internet, when you want to retrieve a document from another computer, you request a service from this computer. Your computer is the client, the computer on which the information you want to access is stored, is called the A common set of standards allows the exchange of data and commands independent from locations, time, and operating systems through the Internet. These standards are called communication protocols, or the Internet Protocol Suite, and are implemented in Internet software. Sometimes the Internet Protocol Suite is erroneously identified with Any information to be transferred is broken down into pieces, so-called packets, and the Internet Protocol figures out how the data is supposed to get from A to B by passing through routers. Each packet is "pushed" from router to router via The technique of breaking down all messages and requests into packets has the advantage that a large data bundle (e.g. videos) sent by a single user cannot block a whole network, because the One of the Internet's (and of the Matrix's) beginnings was the Routing around depends on the location of the interruption and on the availability of intersecting points between networks. If, for example, an E-mail message is sent from Brussels to Athens and in Germany a channel is down, it will not affect access very much, the message will be routed around this damage, as long as a major Internet exchange is not affected. However, if access depends on a single backbone connection to the Internet and this connection is cut off, there is no way to route around. In most parts of the world the Internet is therefore vulnerable to disruption. "The idea of the Internet as a highly distributed, redundant global communications system is a myth. Virtually all communications between countries take place through a very small number of bottlenecks, and the available bandwidth isn't that great," says Douglas Barnes. These bottlenecks are the network connections to neighboring countries. Many countries rely on a one single connection to the Net, and in some places, such as the Suez Canal, there is a concentration of fiber-optic cables of critical importance. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
1896 1896 The Daily Mail was published in Great Britain. It was the first newspaper for the masses. With the emerging of newspapers the manner how politics was perceived by the public changed completely. It became more difficult to keep secrets, while at the same time there was suddenly a new and nearly perfect tool for manipulation. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
John von Neumann b. December 3, 1903, Budapest, Hungary d. February 8, 1957, Washington, D.C., U.S. Mathematician who made important contributions in quantum physics, logic, meteorology, and computer science. His theory of games had a significant influence upon economics. In computer theory, von Neumann did much of the pioneering work in logical design, in the problem of obtaining reliable answers from a machine with unreliable components, the function of "memory," machine imitation of "randomness," and the problem of constructing automata that can reproduce their own kind. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||