Cable internet

Cable Internet is a form of broadband Internet access that uses the cable television infrastructure. Like digital subscriber lines and fiber optic networks, cable Internet bridges the last kilometre or mile from the Internet provider to the subscriber'

Many people who have cable TV can now get a high-speed connection to the Internet from their cable provider. Cable modems compete with technologies like asymmetrical digital subscriber lines (ADSL).

television channel would take up quite a bit of electrical "space," or bandwidth, on a cable. In reality, each television signal is given a 6-megahertz (MHz, millions of cycles per second) channel on the cable. The coaxial cable used to carry cable television can carry hundreds of megahertz of signals.Downstream, which goes toward the user, bit rates can be as much 50 megabits per second for business connections, and two to twenty megabits for consumers depending on the country. Upstream, which goes from the user, rates range from 384Kbit/s to more than 20Mbit/s.

Broadband cable Internet access requires a cable modem at the customer premises and a CMTS (Cable Modem Termination System) at a cable operator facility (typically a headend or hub location).

Putting both upstream and downstream data on the cable television system requires two types of equipment: a cable modem on the customer end and a cable modem termination system (CMTS) at the cable provider's end.

Here are a few cable network terms:
Headend
This is where all cable signals are received, processed, and formatted. The signalsare then transmitted over the distribution network from the headend.

Distribution network
These are relatively small service areas that usually range in size from
100 to 2,000 customers. They’re typically composed of a mixed, fiber-coaxial, or HFC archi-tecture, with optical fiber substituting for the distribution network’s trunk portion. The fiber forms both the connection from the headend and an optical node that changes light to radio frequency (RF)
signals that are then distributed through a coaxial cable throughout the spe-
cific area being serviced.DOCSIS (data over cable service interface specification)All cable modems and like devices have to measure up to this standard.

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The problem is that ISPs often use a fiber-optic network that extends from the cable oper-ator’s master headend, sometimes even to regional headends, out to a neighborhood’s hubsite that then arrives at a fiber-optic node, which serves anywhere from 25 to 2,000 or more homes. (Don’t get me wrong, all links have problems—I’m not picking on cable—really!)
And here’s another issue: If you have cable, open your PC’s command prompt, and type ipconfig and check out your subnet mask. It’s probably a /20 or /21 class B address. Oh my.You already know that’s either 4,094 or 2,046 hosts per cable network connection. Not good!When we say “cable,” we really mean using coax (coaxial) cable for transmission. And CATV, or community antenna television, is now used as a means to offer ost-effective broad-casting to subscribers. Cable is able to provide voice and data, plus analog and digital video,without requiring you to pony up your whole paycheck.Your average cable connection gives you a maximum download speed of 2Mbps. And remember—you have to share that bandwidth with all the other subscribers. As if that weren’t enough, there are other things like overloaded web servers and plain old Net congestion that factor in as well. But your email-checking neighbors really aren’t making that much of a difdifference. So who or what is? Well, if you’re an online gamer, you would likely notice a bit morelag during peak periods

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