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• Cabling 101

  If the computers are in the same room, you can probably skip this section -- Otherwise read on. Most home networks require that additional cabling be installed in the walls as well as the floor or ceiling crawl spaces of your home in order to "network" all the computers. Generally, these cables need to run to a central location in the home where the "hub" is located.
  
  The hub is the connecting point for all the computers. Hubs come in various sizes. The kit advertised contains a four port hub that will connect up to four computers. You can network two computers without using a hub using a "crossover cable" which reverses or flips over the wires inside the cable so the two computers can "talk" to each other without the intermediary hub. The two young adults in my household have their computers connected with a crossover cable so they can play games over their network. Crossover cables are available for about the same cost as a regular cable for Ethernet.

  The most common cabling in today's network is something called CAT5 (Category 5). This data cable types supports 10BaseT Ethernet use. This is a UTP (unshielded-twisted-pair) 4 pair cable that meets certain specifications such as twists-per-inch and other electrical performance specifications. The specifications are very important as with Ethernet, you are moving data over these cables at 10 or 100 megabits a second, which is a lot of data to move in one second and have it arrive intact at the other end. Just being able to do this is in itself a technological marvel!
  
  After you have installed your cable in your home, it must be properly terminated. If you have a professional do it, they will probably terminate it in RJ-45 jack type wall plate. These are very similar to the modular wall connectors used by the phone company but this is where the similarity ends. Once the cables have been installed this way, the cables that came with your "all-in-one-kit" can be used to get from the wall jack to the computer. If you do it yourself, I do recommend some caution here as it is not as easy as it looks. You could also terminate the wires in a wall jack plate, or you could simply bring the cable up through the floor or wall and on out to the computer where you would put an RJ-45 Connector on it (properly) and plug it in to the jack on your network card.
  
  Now the fun part: The terminating of the wire. First off, you need a special tool to handle the "driving" of the little metal contacts down inside the modular connector which puncture the plastic sheathing on the wire and contact the metal conductor inside. This tool can run anywhere from $25 to $400 for one the professionals use. Be careful that you don't buy the $10 tool as they generally only work for 4 conductor telephone cables.

  Secondly, you have to be very careful on spreading the wires out prior to insertion inside the connector before "terminating" the cable in the connector. You can't just line up the pairs of wires side by side, insert them inside, and using the tool, terminate it, even if you do the same thing on both ends of the wire. It's not the same as wiring the phone, which is much more forgiving! There is a specific order or "pinning out" the wire or insertion order within the modular connector. Looking at the jack connection, the connections are numbered 1 through 8 (see picture of connector), left to right. The actual modular connector which is viewed upside down so that the little tab that locks the connector in the jack is down, the connections are numbered in the reverse direction so that 1 is on the right. Now the table:
  
  1 Tx + (transmission)
  2 Tx - (transmission)
  3 Rx + (reception)
  4 Not used - 4 & 5 could be used for data/phone connection but not recommended.
  5 Not used
  6 Rx - (reception)
  7 Not Used
  8 Not Used
  
  Comments: The Tx and Rx connections must be "paired" wires such that you have a TX pair of wires and an Rx pair of wires. The + and - are significant designations and must be observed by strickly observing the color coding on the pairs and not just making sure you use the same pairs but also the same color with the pair. As example, say you had a pair that are orange/white for the TX "pair." In this case, you would probably put the white in the pair to 1 and the orange in the pair to 2.. Is it starting to get complicated? Not really, as long as you do both ends the identically, observing the colors and pairing requirements, and make a good connection made in terminating the wires in the connector. Then it all should work (should?) Inspect your work very carefully as even I have made "bad" terminations in putting the connectors on and I have a very good tool for doing the job! I'll tell you how to test the cable in the next section on using the network card to actually test the cabling.

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