Transition Networks
SM24T6DPA Web User Guide
33664 Rev. B
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10/100BASE-TX MDI and MDI-X Port Pinouts
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 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).
Cable Testing for Existing Category 5 Cable
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 tests are specified in the ANSI/TIA/EIA-TSB-95 Bulletin, “The
Additional Transmission Performance Guidelines for 100 Ohm 4-Pair Category 5 Cabling.”
NOTE
: That when testing your cable installation, be sure to include all patch cables
between switches and end devices
Adjusting Existing Cat 5 Cabling to Run 1000BASE-T
If your existing Category 5 installation does not meet one of the test parameters for
1000BASE-T, there are basically three measures that can be applied to try and correct the
problem:
1.
Replace any Category 5 patch cables with high-performance Category 5e or Category 6
cables.
2.
Reduce the number of connectors used in the link.
3.
Reconnect some of the connectors in the link.
