Currently living in Netherlands, the phone cable of my apartment is a T568 cable which I cannot confirm is A or B yet (will be checked later this evening). However, my ADSL modem only has a handset jack. So how can I wire the cable to the telephone jack provided in the modem package in order to make the modem work?

Since I only use ADSL and no landline at my apartment, it is not necessary to consider how to split the telephone line.


Phone lines only use a single pair. As long as the same wire goes to the same pin on both ends of the RJ11 connector, it will work. Standard pair colors are black/yellow and red/green. A single line uses the two middle pins of the RJ11 connector, but two-line phones will use the inner and outer pairs.

T568A/B only applies to Ethernet connections.

  • Hi @Steven, thanks for your answer. I did some research myself and I read that nowadays sometimes RJ61 is used for multiline telephones. If that is the case, how should I connect that to a normal handset jack? – newbie May 9 '14 at 16:21
  • Normal handset jack will only support a 4-pin RJ11 connector. You can plug a RJ11 into a port meant for RJ45, but not the other way around. – Steven May 9 '14 at 17:48
  • I checked my socket come with the modem package. It turned out to be a 6P4C socket and the cable for the modern is 6P2C (1 red and 1 green). Is it possible to use a 8P8C cable(from the color code my cable has to be one of T568s) to transfer normal single line telephone signal in order to reach a relatively long distance, for instance around 100 m. – newbie May 9 '14 at 19:01
  • The connector has little to no bearing on the distance you can run (at least with POT service), it all depends on the cable used. Large gauge (lower gauge number) wires can be run further. 100m for phone though should work with cat5e or cat3 cable – Steven May 9 '14 at 20:44

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