Cabling Outline
Parts
Network cables consist of three parts, a connector, wires, and an outer jacket. A normal Ethernet Cable or UTP uses a RJ-45 connector, has eight wires in four pairs surrounded by a plastic cylinder. Some cables also have a ripcord to help remove the outer jacket. The wires are twisted together because it causes them to produce less interference on other wires and to have outside interference have less of an effect. (Labeled picture of a half crimped cable)
Types of Network Cables
Variety of Cables
Ethernet cables come in several varieties. The type of cable you'd probably see in home networks today is Cat5e or Cat6 stranded UTP, while the cables going through the walls of a new office building would probably be cat6 solid plenum UTP. They would look the same, but have some note worthy differences.
Cat5e and Cat6 cables both offer the same speeds but Cat6 cable is made to more strict specifications, such as the amount of twists in each pair of wire, which reduces the amount of transmission errors.
Stranded and Solid cables differ in their flexibility. Stranded cables are more flexible so they are a good choice when doing a home installation. Solid cables are stiffer, which (at least in theory) helps reduce the amount of noise they generate and increases network performance, so they're generally used in wall runs.
Plenum cable is designed to be used in a buildings heating vents. Plenum cable's jacket is made of a material that doesn't give of toxic fumes when burned, such as Teflon.
Wiring Specifications
To help keep networks uniform the EIA/TIA-568 Commercial Building Wiring Standard was created. While most of what it deals with isn't important to us, you should follow one of their two pin out patterns when creating your own cables. They are:
- White Green - Green - White Orange - Blue - White Blue - Orange - White Brown - Brown for EIA/TIA-568 A
- White Orange - Orange - White Green - Blue - White Blue - Green - White Brown - Brown for EIA/TIA-568 B
Deviating from these patters could increase the interference caused by crosstalk greatly reducing the functionality of the cable.
Types of Cables
There are three different types of Ethernet cable Straight-Through, crossover, and Rollover. The way to tell these apart is by looking at the pattern of wires on the two ends of the cable. A straight-through cable will have the same pattern at each end, a cross-over cable will have (looking at the bottom of the cable) the first two wires on one end be the third and sixth on the other (or EIA/TIA-568 A on one end and B on the other), and a roll-over cable will have one end the reverse of the other.
When wiring your home network, you should use straight-through cables to connect you computer to a network device, and a crossover cable to connect a network device to another network devices, or a computer to another computer. The only use you could have for a rollover cable is to configure a fairly old router.
| Important! | Most modern equipment can auto-detect the type of cable you're using, so using the wrong type of cable probably will not cause any problems. |