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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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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Claude Chappe built a fixed optical network between Paris and Lille. Covering a distance of about 240kms, it consisted of fifteen towers with semaphores.
Because this communication system was destined to practical military use, the transmitted messages were encoded. The messages were kept such secretly, even those who transmit them from tower to tower did not capture their meaning, they just transmitted codes they did not understand. Depending on weather conditions, messages could be sent at a speed of 2880 kms/hr at best.
Forerunners of Chappe's optical network are the
For more information on early communication networks see
IRC is a text-based chat system used for live discussions of groups.
For a history of IRC see Charles A. Gimon, IRC: The Net in Realtime,
Every computer using
IP numbers are divided into three classes. Class A is restricted for big-sized organizations, Class B to medium-sized ones as universities, and Class C is dedicated to small networks.
Because of the increasing number of networks worldwide, networks belonging together, as
Backbone networks are central networks usually of very high bandwidth, that is, of very high transmitting capacity, connecting regional networks. The first backbone network was the
Virtual Private Networks provide secured connections to a corporate site over a public network as the Internet. Data transmitted through secure connections are encrypted and therefore have to be encrypted before they can be read.
These networks are called virtual because connections are provided only when you connect to a corporate site; they do not rely on dedicated lines and support mobile use.