Hi I have uploaded a simple drawing and I will be buying cables with ends attached can you please tell me in simple terms what the red wall socket is called.
Ok, the box that is on the outside is typically called the Network Interface Device or Demarcation point. The Cat5 E is your Home Run, it goes into the half-ringer/smart-jack(dedicated adsl2+ jack, colored red)
If you look at your cat 5E cable on the plug end, typically the center 2 conductors/contacts have blue and blue white as your pair that is transmitting the dsl signal in this case (in PBX systems this would be for dialtone).
Your setup is for easy repair atleast replacing the homerun.