I believe there are 4 cables inside the UTP cable that are "active" for data, the rest might be for activity and other stuff. I need to know which colors represent the data transfer from an UTP ?

Or am I wrong ? Thanks.

3 Answers 3


Here you go:


  • Perfect! What I wanted.
    – Calavera
    Oct 14, 2011 at 13:46
  • 3
    @Elbow: Beware though that this site only covers network speeds up to 100MBit/s. For Gigabit Ethernet and upwards, all eight wires are used.
    – Sven
    Oct 14, 2011 at 14:08
  • Good point @SvenW
    – Dan
    Oct 14, 2011 at 14:10
  • It should also be noted that in gigE, the pairs don't actually matter that much. The devices that are built to spec should autonegotiate the pinout of each end. We just try to keep it following EIA/TIA 568 standards.
    – Matthew
    Oct 14, 2011 at 14:12
  • True enough but a good sys admin/it guy should really really enforce proper cabling practices. Some manufacturers don't have Auto MDI on by default and that leads to headaches. Personally i always cross then connecting Like devices and use straight through for unlike.
    – ItsGC
    Oct 14, 2011 at 15:23

This site hopefully will provide you with what you need! I belive for standard ethernet cable its pairs 1/2, 3/6, 4/5 and 7/8



It's not black and white. For 10/100 its pairs 1/2 (transmit), and 3/6 (receive) - unless you're using equipment that can autonegotiate. For gigabit, all pairs are used. The above links are all also correct. I'm not sure about 10GigE.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .