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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)
