User's Manual

B-3
Twisted-Pair Cable and Pin Assignments
B
You must connect all four wire pairs as shown in the following diagram to support
Gigabit Ethernet connections.
Figure B-3 Crossover Wiring
1000BASE-T Pin Assignments
All 1000BASE-T ports support automatic MDI/MDI-X operation, so you can use
straight-through cables for all network connections to PCs or servers, or to other
switches or hubs.
The table below shows the 1000BASE-T MDI and MDI-X port pinouts. These ports
require that all four pairs of wires be connected. Note that for 1000BASE-T
operation, all four pairs of wires are used for both transmit and receive.
Use 100-ohm Category 5, 5e or 6 unshielded twisted-pair (UTP) or shielded
twisted-pair (STP) cable for 1000BASE-T connections. Also be sure
that the length
of any twisted-pair connection does not exceed 100 meters (328 feet)
.
Table B-2 1000BASE-T MDI and MDI-X Port Pinouts
Pin MDI Signal Name MDI-X Signal Name
1 Bi-directional Pair A Plus (BI_DA+) Bi-directional Pair B Plus (BI_DB+)
2 Bi-directional Pair A Minus (BI_DA-) Bi-directional Pair B Minus (BI_DB-)
3 Bi-directional Pair B Plus (BI_DB+) Bi-directional Pair A Plus (BI_DA+)
4 Bi-directional Pair C Plus (BI_DC+) Bi-directional Pair D Plus (BI_DD+)
5 Bi-directional Pair C Minus (BI_DC-) Bi-directional Pair D Minus (BI_DD-)
6 Bi-directional Pair B Minus (BI_DB-) Bi-directional Pair A Minus (BI_DA-)
7 Bi-directional Pair D Plus (BI_DD+) Bi-directional Pair C Plus (BI_DC+)
8 Bi-directional Pair D Minus (BI_DD-) Bi-directional Pair C Minus (BI_DC-)
White/Orange Stripe
Orange
White/Green Stripe
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
EIA/TIA 568B RJ-45 Wiring Standard
10/100BASE-TX Crossover Cable
End A
End B
Green
Blue
White/Blue Stripe
Brown
White/Brown Stripe