B Cables

Table B-1. 10/100BASE-TX MDI and MDI-X Port Pinouts

Pin

MDI Signal Name

MDI-X Signal Name

1

Transmit Data plus (TD+)

Receive Data plus (RD+)

 

 

 

2

Transmit Data minus (TD-)

Receive Data minus (RD-)

 

 

 

3

Receive Data plus (RD+)

Transmit Data plus (TD+)

6

Receive Data minus (RD-)

Transmit Data minus (TD-)

4,5,7,8

Not used

Not used

 

 

 

Note: The “+” and “-” signs represent the polarity of the wires that make up each wire pair.

Straight-Through Wiring

If the twisted-pair cable is to join two ports and only one of the ports has an internal crossover (MDI-X), the two pairs of wires must be straight-through. (When auto-negotiation is enabled for any RJ-45 port on this switch, you can use either straight-through or crossover cable to connect to any device type.)

You must connect all four wire pairs as shown in the following diagram to support Gigabit Ethernet connections.

EIA/TIA 568B RJ-45 Wiring Standard 10/100BASE-TX Straight-through Cable

 

 

White/Orange Stripe

 

 

 

Orange

 

 

1

White/Green Stripe

1

End A

2

 

2

 

3

Blue

3

 

4

 

4

 

5

White/Blue Stripe

5

 

6

Green

6

 

7

7

 

 

 

8

White/Brown Stripe

8

 

 

 

End B

Brown

Figure B-2. Straight-through Wiring

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 any RJ-45 port on this switch, you can use either straight-through or crossover cable to connect to any device type.)

You must connect all four wire pairs as shown in the following diagram to support Gigabit Ethernet connections.

B-2

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Image 44
Transition Networks SM24-100SFP-AH manual Straight-Through Wiring, Crossover Wiring, Cables