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Education => Home and Small Office Networking => Topic started by: wednet on October 21, 2022, 01:30:07 PM

Title: Change of cable stops network working
Post by: wednet on October 21, 2022, 01:30:07 PM
Hello

I have 100mb internet at home with Cat5 cables. There are two cables. One from the router to the internal network (RJ45-MMC P2/2) and one from the internal network to my computer (MMC-RJ45). I want to have a fast internet and therefore bought two MMC/RJ45, 1/10GbE, 4x2 cables to replace the cables. When I replace the cable to my computer the internet connection still functions. When I replace the cable from the router I loose internet connection. The internal network is just cables running through my house.

Could someone tell me the best way to find the source of the problem please?

Thanks a lot
Paul
Title: Re: Change of cable stops network working
Post by: icecream-guy on October 21, 2022, 02:28:37 PM
sounds like the cable from service provider to router/modem is not same wiring pinout as the cable that was replaced, check the pins make sure they are same between both cables.
Title: Re: Change of cable stops network working
Post by: wednet on October 22, 2022, 07:28:16 AM
Thanks for the reply. Sorry but I'm not so clued up on this. Are you saying that possibly the composition of the cable doesn't match the connection on one end: either the MMC or RJ45 end? If so can you tell me what I should look for please or should I ask the cable supplier? The old ones (2x2 cables) work and they told me to get these, but they only know the cables and not my devices.

Thanks and sorry if that doesn't make sense.
Title: Re: Change of cable stops network working
Post by: icecream-guy on October 22, 2022, 07:53:41 AM
the RJ45 cables are made up of 4 pairs of wires, each of the 8 wires, go to a specific pin. like in the example picture I attached, so if the pin outs do not match between cables (specifically the transmit and receive pins)  there cannot be communications across the wire.  the picture attached may or may not be same as your cables, it is just an example.
Title: Re: Change of cable stops network working
Post by: wednet on October 22, 2022, 12:37:48 PM
It's interesting. The RJ45 setup on the new cable is different to the MMC/RJ45 I have that works but is the same as other RJ45/RJ45 cables I have. Would that match to your explanation? Thanks.
Title: Re: Change of cable stops network working
Post by: icecream-guy on October 23, 2022, 06:10:59 AM
There is another EIA-TIA wiring standard 568B,  568A is above as shown,  568B is below.
Title: Re: Change of cable stops network working
Post by: icecream-guy on October 23, 2022, 06:12:28 AM
and just to note, that isf one side is EIATIA 568A and the other side is EIATIA 568B, that makes a crossover cable.