Appendix B Cabling Guidelines

UTP Cable Wiring

100BASE-TX unshielded twisted-pair cables can be wired as "Straight- Through" or, in some cases, "Crossover" depending on the application. For workstations connected to a hub, use "Straight-Through' wiring illustrated in Table B-1. In some instances, you may want to use "Crossover" wiring illustrated below in Table B-2.

"Straight-Through" Cable Wiring

Pin Number		Pin Number
1	(TRX +)	1	(TRX +)
2	(TRX -)	2	(TRX -)

3	(RCV +)	3	(RCV +)

6	(RCV -)	6	(RCV -)

4, 5, 7, 8		Not Used

Crossover”

Cable Wiring

Pin Number		Pin Number
1	(TRX +)	3	(RCV +)
2	(TRX -)	6	(RCV -)

3	(RCV +)	1	(TRX +)

6	(RCV -)	2	(TRX -)

4, 5, 7, 8		Not Used

Table B-1. Straight-Through Wiring

Table B-2. Crossover Wiring

Cable Wiring Standards

There are two governmental agencies: the Electronic Industry Association (EIA) and the Telecommunications Industry Association (TIA), which set the standard for all cable wiring requirements for commercial buildings. For 100BASE-TX networks, Category (CAT) 5 should be used.

With the advent of 100Mbit network products, it is best to use higher quality CAT 5 cables like Belden or Helix as well as CAT 5-compliant patch panels and connectors while following the EIA/TIA wiring standards. 100 Ohm UTP/STP CAT 3, 4 & 5 type cables use 4-pair UTP wiring.

Refer to the illustrations on page 12 for standard 100BASE-TX wiring and 4- pair 100Mbit wiring using either T568A (Table B-3) or T568B (Table B-4) wiring standards. Both T568A and T568B wiring configurations are compatible with 10BASE-T and 100BASE-TX and require no special hardware configurations. However, it is highly recommended that only one wiring scheme be used in premise wiring to avoid potential problems.

KNExTX/WG User’s Guide - Rev. A00

Kingston Technology Company