66
Frequently Asked Questions (continued)
What type of cable should I be using? (continued)
What´s the difference between a crossover cable and a straight-through 
cable?  
The wiring in crossover and straight-through cables are different. The two 
types of cable have different purposes 
for different LAN configurations. EIA/TIA 
568A/568B define the wiring standards 
and allow for two different wiring color 
codes as illustrated in the following 
diagram. 
 
*The wires with colored backgrounds may 
have white stripes and may be denoted 
that way in diagrams found elsewhere.
How to tell straight-through cable from 
a crossover cable: 
The main way to tell the difference 
between the two cable types is to 
compare the wiring order on the ends 
of the cable. If the wiring is the same on 
both sides, it is straight-through cable. If one side has opposite wiring, it is a 
crossover cable.
 
All you need to remember to properly configure the cables is the pinout order of 
the two cable ends and the following rules: 
A straight-through cable has identical ends 
A crossover cable has different ends
 
It makes no functional difference which standard you follow for straight-through 
cable ends, as long as both ends are the same. You can start a crossover cable 
with either standard as long as the other end is the other standard. It makes no 
functional difference which end is which. The order in which you pin the cable 
is important. Using a pattern other than what is specified in the above diagram 
could cause connection problems.
 
When to use a crossover cable and when to use a straight-through cable: 
Computer to Computer – Crossover 
Computer to an normal port on a Hub/Switch – Straight-through 
Computer to an uplink port on a Hub/Switch - Crossover 
Hub/Switch uplink port to another Hub/Switch uplink port – Crossover 
Hub/Switch uplink port to another Hub/Switch normal port - Straight-through 
 
 
Why can´t I access the web based configuration? (continued)