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LatencyInternet traffic travels at the speed of light. That means that a request from a web-surfer in California to a web server in New York takes about 0.03 seconds (30 milliseconds) to make the round trip. In practice, because the request may pass through a dozen or more routers and switches, each with some delay, it will average about 90 milliseconds for a good connection.
With satellite connections the distances are so vast that even light speed isn't fast enough to not be noticeable. The satellites used are 22,000+ miles above the equator, so the round trip in on the order of 95,000 miles from North America. That means there will be a round trip of over 500 milliseconds, not counting the normal Internet switching and routing. The satellite switches are also relatively slow (they route the signal between up and downlinks), so that the fastest possible connection is about 650 milliseconds.
This time lag is called latency, and is used to explain some of the problems for such Internet uses as VoIP and real-time gaming.
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