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SATELLITE


Satellite internet involves upstream (outgoing) and downstream (ingoing) data is sent between the computer and a satellite. The subscriber's hardware includes a satellite dish and a transceiver (transmitter/receiver) that communicates in microwaves. In a two-way satellite Internet connection, the upload usually sent at a slower speed than the download data. Thus, the connection is asymmetric (unequal upload/download rates). The satellite dish antenna transmits and receives signals. Uplink speeds are usually 50 to 150 Kbps for a subscriber using a single computer. The downlink occurs at speeds ranging from about 150 Kbps to more than 1200 Kbps, depending on factors such as Internet traffic, the capacity of the server, the atmospheric conditions (weather) (not such a major in terms of satellite but more in terms of wireless), and the sizes of downloaded files.


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Satellite Internet is an excellent, although rather expensive, solution for people in rural areas where Digital Subscriber Line (DSL) and cable modem connections are not available (like my house. I mean, they can't even deliver pizza here! How uncivilized is that?!). The two-way satellite Internet option offers an always-on connection that bypasses the dial-up process. In this respect, the satellite system resembles a cable modem Internet connection. But this asset can also be a liability, unless a firewall is used to protect the computer against hack attempts.
The nature of the satellite connection (high capacity/speed) is good for Web browsing and for large amounts of downloading of files. Because of long latency compared with purely land-based systems, interactive applications such as online gaming are not compatible with satellite networks. In a two-way geostationary-satellite (a fancy term for a satellite that follows the Earth's revolution so that it positions itself above a particular spot all the time...or in the case of Sky, MOST of the time) the speed is such that it theoretically takes 0.48 seconds for an electromagnetic signal to make two round trips around the earth - 186,000 miles - to and from the satellite (but in reality somewhat longer). Satellite systems are also prone to rain fade (degradation during heavy precipitation...whatever that means) and occasional brief periods of solar interference in mid-March and late September, when the sun lines up with the satellite for a few minutes each day (which is suppose to affect it in some complicated scientific way). Rain fade and solar interference affect all satellite links from time to time, not just Internet systems.



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