Black Box TS029A-R4 Manual page 19

Summary Twisted Pair (TP) Wire Connection Chart
Twisted Pair cables connecting:
PC to Hub/Switch Straight thru
PC to PC Crossover
Hub/Sw to Hub/Switch Crossover
Note: Because the Base-T standard has a mix of crossover and
straight thru cables, many opportunities arise for the pairs to get
"flipped." The TVR1000 3 jacks can quickly simulate a straight thru
and crossover connection to test for the proper cabling solution.
USOC vs AT&T Wiring Configurations Of all the combinations
of 8 position modular connector wiring schemes, two have become
popular enough to gain name recognition status. Of the two, only
"AT&T" can be used for 10, 100, 1000 Base-T systems. The differ-
ence is the pairing of signals on the cable (pairs are twisted together
for noise immunity).
USOC paired configuration. A standard for telephones, this
●
configuration is never used to connect network devices. The
pinouts do not match what is required for Ethernet.
AT&T paired configuration (also known as AT&T 258A, EIA
●
(TIA) 568B, Twisted Pair Networks). The older 10Base-T
standard defined and required pairs 1, 2 and 3, 6 to be wired but
all new cabling almost always includes the other two pairs (4,5
and 7,8). This is because some 100 Base-T schemes and all
1000 Base-T schemes use all 4 pairs. A "crossover" version of
"AT&T" is also quite common. Both straight thru and crossover
diagrams are shown.
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AT&T 258A (EIA/TIA 568B) STRAIGHT THRU
PIN #
1
2
3
6
4
5
7
8
Colors: First color is the base color of the cable. The second color is
the stripe on the cable.
AT&T 258A (EIA/TIA 568B) CROSSOVER
PIN #
1
2
3
6
4
5
7
8
PIN # WIRE COLOR
1 Orange/White
2 Orange
3 Green/White
6 Green
4 Blue
5 Blue/White
7 Brown/White
8 Brown
PIN # WIRE COLOR
3 Orange/White
6 Orange
1 Green/White
2 Green
4 Blue
5 Blue/White
7 Brown/White
8 Brown
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