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Old 12-09-2013, 06:22 PM   #1
rey
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gigabit LED indicator is always turned off, turns on with a different cable


hello
i have a tp-link gigabit switch, it has the common led lights that
indicate gigabit speed, if i use a factory cable that came with another router it turns on the gigabit led, however if i use a CAT 5e cable i built myself with standard B wiring it doesn't turn on, i can't find any differences other than the fact that i built the cable from standard parts from the store, the 'good' cable came in a box with some other router,

i think i'm missing some step in the procedure to build the cables but i can't figure it out what is it, the cable works good

so whats the difference between an ethernet cable from factory and a home made cat 5e cable that makes the gigabit LED turn on for the factored cable??

thanks for your help
 
Old 12-09-2013, 07:02 PM   #2
michaelk
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Most likely a wiring problem. Have you checked the cable with an ohm meter or simple cable checker?

10/100 only uses 2 pairs vs 1000 which needs all 4. (pins 4,5,7,8 are unused in 10/100). Even if the cable checks out ok at DC it may not work at MHz speeds. Did you keep the wires twisted as much as possible? May not of been crimped correctly.
 
Old 12-09-2013, 09:24 PM   #3
rey
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i checked with a two piece cable tester, all four leds lighted on both pieces of the tester, everything works normal but the negotiation, it seems to set it to 100 mbps all the time just because of the cable, the switches and routers are unable to get the gigabit speed automatically
the cable box (300 meters) says cat 5e cable
tomorrow i will try to crimp the plugs harder, to get the little copper pins deeper

any other ideas on this?? any special crimping technique or wiring or something like that?

thanks for your help!
 
Old 12-10-2013, 11:02 AM   #4
michaelk
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Make sure the cable is wired correctly i.e. color is pin for pin.
Make sure the individual pairs are twisted together but separate from the others.
 
Old 12-10-2013, 02:29 PM   #5
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All the wires need to be OK for gig speeds. Not only do the wires need to be fully connected they also need to be almost without damage.


I doubt crimping harder will help.

You need a TDR or more advanced tester for proper tests.

Cat 5e may not like the length that you have or your nic/switch doesn't have full power to send that far.
 
Old 12-10-2013, 02:42 PM   #6
rey
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i found that one of the computers negotiaties to 100 mbs and this makes two of the switches do the same, then other computers connected to the second, cascaded switch would negotiate to 100 mbps, interesting effect!!!!
 
Old 12-12-2013, 06:16 PM   #7
jefro
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Oddly some of the most expensive network brand stuff can't seem to auto worth a darn. We just set it so it can't do what it wants.

Thanks for the update.
 
  


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