* 28AWG (CCA) silver satin jacket
* Terminated with RJ11 (6P4C) plug on both end
* 4 conductor 

Straight wiring is generally used for data application.
pin1 -- pin1 (black)
pin2 -- pin2 (red)
pin3 -- pin3 (green)
pin4 -- pin4 (yellow)

Reverse wiring is generally used for voice application
pin1 -- pin4 (black)
pin2 -- pin3 (red)
pin3 -- pin2 (green)
pin4 -- pin1 (yellow)