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The Internet Via Cable

Using cable Internet services for the first time can be a breathtaking experience. Images and text flash before your eyes instantly. Full-motion video and audio play without jitter. When you see this, you realize that this was how the Internet was meant to be. Even for Internet oldtimers, it's like a whole new world.

The cable television network has emerged as the early leader in providing such high-speed data access in the home. With more than a million cable modern subscribers now in North America, the system has matured from a string of experimental deployments in 1995 to a mainstream service available in most major cities.

Internet access over cable runs at speeds up to 100 times those of the traditional dial-up world. This raw speed is the catalyst producing the dramatic change to typical Internet services. And the connection is "always on," enabling users to call up a site immediately as the spirit moves them. Gone are the days of having to log in to the network.

How does cable achieve these data rates? In the late 1980s and early 1990s cable operators started deploying fiber optics in their networks. Cable companies ran fiber out to individual neighborhoods and made use of existing network of coaxial cable to reach the "last mile" to each home. The optical fibers connect the cable operator's central facility (the "head end") to each neighborhood area (the "node"). Fiber has greatly increased the capacity and reliability of cable TV networks. With a cable Internet connection, data occupy the space of one TV channel. Tune to this channel with your TV, and you'll see only static, but connected to your cable modem it becomes a data stream flowing at about 40 megabits per second (Mbps), which can then be relayed to your personal computer at rates up to 10 Mbps. the fiber network also allow signals to be sent back from the home to the head end, making telephone and interactive vidio services possible.  

       
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