Standard, Straight-Through Wiring (both ends are the same):
RJ45 Pin # |
Wire Color |
Wire Diagram |
10Base-T Signal |
1000Base-T Signal |
1 |
White/Green |
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Transmit+ |
BI_DA+ |
2 |
Green |
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Transmit- |
BI_DA- |
3 |
White/Orange |
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Receive+ |
BI_DB+ |
4 |
Blue |
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Unused |
BI_DC+ |
5 |
White/Blue |
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Unused |
BI_DC- |
6 |
Orange |
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Receive- |
BI_DB- |
7 |
White/Brown |
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Unused |
BI_DD+ |
8 |
Brown |
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Unused |
BI_DD- |
Straight-Through Cable Pin Out for T568A
RJ45 Pin # |
Wire Color |
Wire Diagram |
10Base-T Signal |
1000Base-T Signal |
1 |
White/Orange |
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Transmit+ |
BI_DA+ |
2 |
Orange |
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Transmit- |
BI_DA- |
3 |
White/Green |
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Receive+ |
BI_DB+ |
4 |
Blue |
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Unused |
BI_DC+ |
5 |
White/Blue |
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Unused |
BI_DC- |
6 |
Green |
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Receive- |
BI_DB- |
7 |
White/Brown |
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Unused |
BI_DD+ |
8 |
Brown |
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Unused |
BI_DD- |
Straight-Through Cable Pin Out for T568B
Pair 1 (T1 & R1)
Usually the primary dial tone or talk circuit is wired to the center two pins (pins 3 & 4) and is the white/blue and blue/white pair (AKA: T1 & R1 – tip 1 and ring 1). A standard single line phone draws dial tone from these center pins.
NOTE: The type of wiring shown here is known as USOC (pronounced U-sock). See background below.
The multi-conductor cables attached to RJ11 connectors usually have colored sheaths.
position |
RJ25 pin |
RJ14 pin |
RJ11 pin |
Pair |
T/R |
± |
Cat 5e/6 colors |
Colors |
Old colors |
1 |
1 |
3 |
T |
+ |
white/green |
white/green |
white |
||
2 |
2 |
1 |
2 |
T |
+ |
white/orange |
white/orange |
black |
|
3 |
3 |
2 |
1 |
1 |
R |
– |
blue |
blue/white |
red |
4 |
4 |
3 |
2 |
1 |
T |
+ |
white/blue |
white/blue |
green |
5 |
5 |
4 |
2 |
R |
– |
orange |
orange/white |
yellow |
|
6 |
6 |
3 |
R |
– |
green |
green/white |
blue |