• zackhow@programming.dev
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      1 day ago

      Crossover, but it isn’t needed anymore since most modern devices can detect what they are connected to and adjust.

      • Feidry@sh.itjust.works
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        1 day ago

        Well there was A and B and it’s been long enough since I made any cable, I don’t remember which one everyone uses and which one only weirdos use.

        • netweirdo@lemmy.zip
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          1 day ago

          T568B is the one everyone uses while T568A is the odd one.

          I don’t get what’s particularly bad about T568A though? I was told it’s just plain worse than T568B for anything faster than gigabit and I swear I never saw any store bought cables using it.

          • Zanathos@lemmy.world
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            1 day ago

            The configuration has absolutely no bearing on performance. It is purely for standardization. Straight through cables work with either because it’s literally just connecting the copper on either end. The difference between A and B is just flipping 2 pairs around although I forget which. Only 4 or 5 cables of 8 are even used to this day which is crazy.

            • adjectivenoun@lemmy.world
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              22 hours ago

              There are 4 pairs of 2 wires, for 8 overall. They are all used, but the pairs are redundant. From what I understand, when you send a positive pulse on, say, the solid blue wire, you also send a negative pulse on the stripy blue and white wire. The twisted pairs should counteract any interference, but if it doesn’t, the arrival of the bumps with opposite polarity should foolproof things a little.

              Oh yeah it’s called differential signalling.