Switch User Manual

C ABLES
B-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 the RJ-45 port on the CPE, you can use
either straight-through or crossover cable to connect to any device type.)
Figure B-3 Crossover Wiring
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.
White/Orange Stripe
Orange
White/Green Stripe
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
EIA/TIA 568B RJ-45 Wiring Standard
10/100BASE-TX Crossover Cable
End A
End B
Green
Blue
White/Blue Stripe
Brown
White/Brown Stripe