Black Box LPB2910A - Crossover Wiring; 1000 BASE-T Pin Assignments

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Chapter 9: Cables
Figure 9-2. EIA/TIA 568B RJ-45 wiring standard 10/100BASE-TX straight-through cable.
9.4 Crossover Wiring
If the twisted-pair cable is to join two ports and either both ports are labeled with an “X” (MDI-X) or neither port is labeled with
an “X” (MDI), a crossover must be implemented in the wiring. (When auto-negotiation is enabled for any RJ-45 port on this
switch, you can use either straight-through or crossover cable to connect to any device type.)
You must connect all four wire pairs as shown in the following diagram to support Gigabit Ethernet.
Figure 9-3. EIA/TIA 568B RJ-45 Wiring Standard 10/100BASE-TX Crossover Cable.
9.5 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 328 feet (100 meters).
Table 9-2. 1000BASE-T MDI and MDI-X 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-)