MDI crossover cable indicator port color - DTX-NSM | Fluke Networks

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MDI crossover cable indicator port color - DTX-NSM

The Network Connectivity test can identify if a crossover cable has been used. The port colors indicated by the switch icon will display in either green or orange color.
 
The crossover indicator port color (twisted pair only):
 
Green Port Color
If the switch icon is green in color, either the cable is straight through, or the cable is a crossover and the hub or switch crossed pairs 12-36 (MDI on the Negotiation Details screen).
 
Orange Port Color
If the switch icon is orange in color, the DTX compensated for a crossover cable by crossing pairs 12-36 (MDI-X on the Negotiation Details screen).

Whether the link partner is determined to be an MDI (a PC, or "normal" connection), or an MDI-X (a hub/switch, or "uplink" connection) is traditionally determined by whether the TX signal is sensed on pair 1,2 or pair 3,6.

Most modern hubs and switches are capable of auto-sensing the attached link partner's signal, and will accommodate either by internally switching which pair is used by the hub/switch. The sensing is usually accomplished by the simple expedient of alternately offering the TX signal on each of the two pair choices.

    

 
The Negotiation Details screen also displays the MDI Crossover Status.

      

Author: Adrian Young

Creation Date: 2014-02-20

Last Modified: 2014-02-20