Module 1.1: Ethernet cables

If you want to learn about driving, you first have to understand what a road is.
In this case, network "roads" are cables, but can also be fiber optics or wireless networks
We need to understand how to create one of these "roads" from scratch
We will be using either category 5 "cat5" or category 6 "cat6" cables
cat5 has a max speed of 1 gb/s, especially if it is labeled cat5e, or cat5 extended
cat6 has a max speed of 10 gb/s
The cable ends for these are not interchangeable, as one wire is a bit thinner than the other (cat5 is 24AWG while cat6 is 23AWG, a bit thicker)
The ends are called RJ45 and has 8 slots
When viewed with the flat side towards you, these are the colors:

This is NOT random
The first two orange pairs (1 and 2) are for data transmit
The green pairs (3 and 6) are for data receive
The blue pair is for power over ethernet (POE) plus (+)
The brown pair is for POE negative (-)
This color is different from 8 conductor (4 pair) telephone cables which may look exactly alike
Reason? Phone cables start with 4-5 as line one, then 3-6 as line two, 2-7 as line three and 1-8 as line four
Each of these has up to 90 volts on each pair (when a telephone rings) so we separate our color code for computers
Reason? Plugging a computer into a phone outlet will not burn out the network card on the computer this way

Migrated from Apple Server Wiki. Original page ID: V6c8B7u