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1000base-t cable requirements – SMC Networks TIGERSWITCH SMC8648T User Manual

Page 61

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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 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 802.3ab 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.”

Note that when testing your cable installation, be sure to include all patch
cables between switches and end devices.

Table B-2. 1000BASE-T MDI-X and MDI Port Pinouts

Pin

MDI-X Signal Name

MDI Signal Name

1

Bi-directional Data Two Plus (BI_D2+)

Bi-directional Data One Plus (BI_D1+)

2

Bi-directional Data Two Minus (BI_D2-)

Bi-directional Data One Minus (BI_D1-)

3

Bi-directional Data One Plus (BI_D1+)

Bi-directional Data Two Plus (BI_D2+)

4

Bi-directional Data Four Plus (BI_D4+)

Bi-directional Data Three Plus (BI_D3+)

5

Bi-directional Data Four Minus (BI_D4-)

Bi-directional Data Three Minus (BI_D3-)

6

Bi-directional Data One Minus (BI_D1-)

Bi-directional Data Two Minus (BI_D2-)

7

Bi-directional Data One Plus (BI_D3+)

Bi-directional Data One Plus (BI_D4+)

8

Bi-directional Data Three Minus (BI_D3-)

Bi-directional Data Four Minus (BI_D4-)

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