Crossover Cables

What is the significance in TX+ and TX- as well as RX+ and RX-?

Can one create an Ethernet crossover cable by using the following pin-out?

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63245178

instead of the TIA/EIA standard:

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36145278

Also, can one make a T1 crossover by using the following pin-out?

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54321678

instead of the standard:

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I only ask because a technician in CO wired a T1 crossover for the implementation of an inline ASE, with the TX and RX pairs crossed. I was wondering if this will cause any problems in the future, it seems to be working fine now. I am a few hundred miles away, or I would go swap it out myself.

His work log states that he created a cable with the following pin out:

w/gr -- gr -- w/o -- bl -- w/bl -- o -- w/br -- br
w/bl -- bl --w/o -- gr -- w/gr -- o -- w/br -- br

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Comments

Priston

I don't understand why technicians wire stuff the wrong way -.- So annoying when the 66 block is backwards.

I got a feeling your routers and switchs auto-detected what pairs are what.

Monkerz

Priston wrote: »

I got a feeling your routers and switchs auto-detected what pairs are what.

I was in hopes that was the case, but I see now the SEFS are counting up slowly. I am going to overnight the branch a correct T1 crossover.