Alcatel-Lucent ls 6248 Quick Setup Guide

B-30

Cables

B

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).

Installed Category 5 cabling must pass tests for Attenuation, Near-End Crosstalk 
(NEXT), and Far-End Crosstalk (FEXT). This cable testing information is specified in 
the ANSI/TIA/EIA-TSB-67 standard. Additionally, cables must also pass test 
parameters for Return Loss and Equal-Level Far-End Crosstalk (ELFEXT). These 

1

Receive Data plus (RD+)

Transmit Data plus (TD+)

2

Receive Data minus (RD-)

Transmit Data minus (TD-)

3

Transmit Data plus (TD+)

Receive Data plus (RD+)

6

Transmit Data minus (TD-)

Receive Data minus (RD-)

4,5,7,8

Not used

Not used

Note: The “+” and “-” signs represent the polarity of the wires that make 

up each wire pair.

1

Bi-directional Data One Plus (BI_D1+)

Bi-directional Data Two Plus (BI_D2+)

2

Bi-directional Data One Minus (BI_D1-)

Bi-directional Data Two Minus (BI_D2-)

3

Bi-directional Data Two Plus (BI_D2+)

Bi-directional Data One Plus (BI_D1+)

4

Bi-directional Data Three Plus (BI_D3+)

Bi-directional Data Four Plus (BI_D4+)

5

Bi-directional Data Three Minus (BI_D3-)

Bi-directional Data Four Minus (BI_D4-)

6

Bi-directional Data Two Minus (BI_D2-)

Bi-directional Data One Minus (BI_D1-)

7

Bi-directional Data One Plus (BI_D4+)

Bi-directional Data One Plus (BI_D3+)

8

Bi-directional Data Four Minus (BI_D4-)

Bi-directional Data Three Minus (BI_D3-)