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B-5
1000BASE-T Cable Requirements
All Category 5 UTP cables that are used for 100BASE-TX connections
should also work for 1000BASE-T, providing that all four wire pairs are
connected. However, it is recommended that for all critical connections, or
any new cable installations, Category 5e (enhanced Category 5) or
Category 6 cable should be used. The Category 5e and 6 specifications
include test parameters that are only recommendations for Category 5.
Therefore, the first step in preparing existing Category 5 cabling for
running 1000BASE-T is a simple test of the cable installation to be sure
that it complies with the IEEE 802.3-2005 standards.
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.”
Table B-2 1000BASE-T MDI and MDI-X Port Pinouts
Pin MDI Signal Name MDI-X Signal Name
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 Four Plus (BI_D4+) Bi-directional Data Three Plus (BI_D3+)
8 Bi-directional Data Four Minus (BI_D4-) Bi-directional Data Three Minus (BI_D3-)
