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satelliteWith some digital TV standards over satellite, it is possible to get Internet access. DirecTV is one well known satellite internet product. The key limitation of commercial TV/internet satellites is the upstream capability... The TV satellite technology now in use is not suited to receiving weak signals that any small home unit could produce, so instead, the satellite listens to its base stations for instructions on what to send, and all users get that, and decide whether it is meant for them, or just discarded. The link from you to the internet, for example a request to get www.netscape.com, must travel over more mundane technology: a phone line, and a plain old fashioned modem. One other disadvantage of satellite is the high latency inherent in such a link. This is a function of the sheer distance between you and the geo-syncronous satellite. Users of DirecTV report data arrives in bursts, of, say, 10-20 seconds, then there is a pause. This makes it technically faster than ISDN and low-end DSL, but practically speaking, slower. Of course if your area is devoid of alternatives, DirecTV will be the only choice!
latencyLatency is also referred to as ping time, it is the time it will take a single packet of data to travel to a remote server, and return. Latency improves in proportion to line speed, (and faster speeds provide more bandwidth). Although, with a sufficiently small packet, the ping time is more a function of the number of hops between you and the remote server, congestion on the way, and so on. On a modem, ping time to your first hop (usually your ISP modem rack), is no better than 100ms (1/10th of a second). With larger packets, say, 2K, this could be around 1000ms (1 second) or more. Players of any internet interactive games know that latency is a key factor in deciding which game to join and how well it will play.
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