said by InvalidError:Except that last 5-10m is where you will run into the most problems with nearby electrical that cat. 3 may not overcome. said by planiwa:
My assumption was that they use something like CAT6e nonstop from Demarc to modem jack.
The 50-1200m between your demarc and the DSLAM is Cat3 or equivalent, there is no point in using Cat6e or even plain Cat5 for the last 5-10m.