Peripherals and Networking - Strata Study Guide - page 98

There are different categories of UTP cables. The higher the category number, the better
the cable can conduct data at a high speed. For example, Category 5 (Cat5) cable can
carry data at up to 100 Mbps. Cat5e cable can carry data at up to 1 Gbps, and Cat6 cable
can carry data at 10 Gbps. (Those are just the maximum transfer rates that the cables can
support with an adequate level of accuracy; the cables are passive and don't control the
data transmission rate.)

Standard and Crossover Cables

The way the individual wires in a cable are connected into the connectors on each end is
known as the cable's pin out. On standard network cables, it's a straight-through pin out,
so that the wire colors are in the same order at each end of the cable. If you look at any
UTP Ethernet cable, for example, you'll see that the orange wires are in the same place
on both ends. Standard cables like that are used to connect devices such as printers and
computers to the switch or router.

A crossover cable , less common but still very important, connects two similar devices,
such as the sockets on patch-panels (panels that connect networks). You may use one to
connect two routers or switches, for example, or one laptop to another laptop. Another
name for this cable type is patch cable . If you look at the ends of one of these cables,
you'll notice that the order of the colored wires is reversed on one end.

EXERCISE 3.8

Compare Ethernet and Phone Cables
1.

Locate an Ethernet cable and a telephone cable.

2. Looking at the plugs at the ends of the cable (which are usually translucent), count the

number of wires in each cable. For an Ethernet cable, there are eight. For a telephone
cable, there are either two (for a single-line cable, an RJ-11 plug) or four (for a dual-line
cable, an RJ-14 plug).

Powerline Ethernet (HomePlug)
In a large home or offi ce, where computers are spread out over multiple fl oors and rooms,
running Ethernet cable often isn't practical. One solution is to use wireless networking,
as discussed later in this chapter. If wireless networking isn't an option for some reason,
though, Powerline Ethernet , aka HomePlug , may be an attractive alternative.
Powerline Ethernet uses the electrical wiring in your home or offi ce to carry network
traffi c, sharing those existing wires with the electricity being delivered through them. You
buy Powerline adapters (see Figure 3.13) that plug into any electrical outlet (avoiding those