Suse Linux 9.3 For Dummies- P10

Suse Linux 9.3 For Dummies- P10:This part is all about getting you started on your wayto a lasting relationship with SUSE Linux. Before youcan begin your SUSE Linux experience, I spend a chapterexplaining what SUSE Linux is and what you can do withSUSE Linux (pretty much anything you can do with a PCthat runs Windows).
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Suse Linux 9.3 For Dummies- P10 Chapter 7: I Want My Internet, Now! 115 Cable company To Internet head end (the central backbone distribution point) Cable Modem Termination System (CMTS) A neighborhood (one or more homes with cable modems) Another neighborhood (all homes with cable modems share same cable) Ethernet card in PC Figure 7-4: Cable From modems cable 11 0 10 provide TV 10 high-speed 0 Internet access over the cable TV Cable Modem Your PC network. The coaxial cable that carries all those hundreds of cable TV channels to your home is a very capable signal carrier. In particular, the coaxial cable can carry signals covering a huge range of frequencies — hundreds of megahertz (MHz). Each TV channel requires 6 MHz — and the coaxial cable can carry hundreds of such channels. The cable modem places the upstream data in a small frequency band and expects to receive the downstream data in a whole other frequency band.Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. 116 Part II: Test Driving SUSE At the other end of your cable connection to the Internet is the Cable Modem Termination System (CMTS) — also known as the head end — that your cable company installs at its central facility. (Refer to Figure 7-4.) The CMTS con- nects the cable TV network to the Internet. It also extracts the upstream digi- tal data sent by your cable modem (and by those of your neighbors as well) and sends all of it to the Internet. The CMTS also puts digital data into the upstream channels so that your cable modem can extract that data and pro- vide it to your PC via the Ethernet card. Cable modems can receive downstream data at the rate of about 30 Mbps and send data upstream at around 3 Mbps. However, all the cable modems in a neighborhood share the same downstream capacity. Each cable modem filters out — separates — the data it needs from the stream of data that the CMTS sends out. Cable modems follow a modem standard called DOCSIS, which stands for Data Over Cable Service Interface Specification. You can buy any DOCSIS-compliant modem and use it with your cable Internet service; all you have to do is call the cable company and give them the modem’s identify- ing information so that the CMTS can recognize and initialize the modem. In practice, with a cable modem you can get downstream transfer rates of around 1.5 Mbps and upstream rates of 128 Kbps. These are maximum rates, and your transfer rate is typically lower, depending on how many users in your neighborhood are using cable modems at the same time. If you want to check your downstream transfer speed, go to bandwidth place.com/speedtest and click the link to start the test. For my cable modem connection (for example), the tests reported a downstream transfer rate of about 1.4 Mbps. Typical cable modem setup To set up cable modem acc ...