Acessing the Internet

The Net connections can be based on wire-line and wireless access technolgies.

Wire-line access

Wire-less access

copper wires

Satellites

coaxial cables

mobile terrestrial antennas

electric power lines

fixed terrestrial antennas

fiber-optic cables







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 ISDN lines, etc., to an Internet Service Provider, from there, via fibre-optic cables, to the nearest Internet exchange, and on into a backbone network, tunneling across the continent und diving through submarine fibre-optic cables across the Atlantic to another Internet exchange, from there, via another backbone network and across another regional network to the Internet Service Provider of the supposed message recipient, from there via cables and wires of different bandwidth arriving at its destination, a workstation permanently connected to the Internet. Finally a sound or flashing icon informs your virtual neighbor that a new message has arrived.

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 Intelsat, Intersputnik and Inmarsat.

Scheduled privatization of intergovernmental satellite consortia:

Satellite consortia

Year of foundation

Members

Scheduled date for privatization

Intelsat

1964

200 nations under the leadership of the USA

2001

Intersputnik

1971

23 nations under the leadership of Russia

?

Inmarsat

1979

158 nations (all members of the International Maritime Organization)

privatized since 1999

Eutelsat

1985

Nearly 50 European nations

2001



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

Project name

Main investors

Expected cost

Number of satellites

Date of service start-up

Astrolink

Lockheed Martin, TRW, Telespazio, Liberty Media Group

US$ 3.6 billion

9

2003

Globalstar

13 investors including Loral Space & Communications, Qualcomm, Hyundai, Alcatel, France Telecom, China Telecom, Daimler Benz and Vodafone/Airtouch

US$ 3.26 billion

48

1998

ICO

57 investors including British Telecom, Deutsche Telecom, Inmarsat, TRW and Telefonica

US$ 4.5 billion

10

2001

Skybridge

9 investors including Alcatel Space, Loral Space & Communications, Toshiba, Mitsubishi and Sharp

US$ 6.7 billion

80

2002

Teledesic

Bill Gates, Craig McCaw, Prince Alwaleed Bin Talal Bin Abdul Aziz Alsaud, Abu Dhabi Investment Company

US$ 9 billion

288

2004


Source: Analysys Satellite Communications Database

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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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