As part of refurbishing the house, I'm putting in cat6 shielded twisted
pair cable.

I've gone for Cat 6 STP able as there will be co-axial and mains cables
nearby in the plastered walls, and also for future proofing.

I have had problems in the past with computers causing interference on
my Sky boxes which was only cured by moving the network cables and
co-axial cables further apart.

I currently have a Netgear GS748 48 port gigabit switch.

This Cat6 STP cable has a foil covering and there is a ninth bare wire
and is helpfully called the drain wire....

Now my question is what is this drain wire typically connected to at
both ends?

At the socket end, Is it the metal back boxes or do I have to buy STP
cat 6 rated euro modules that will have a ninth punch down terminal for
the drain wire?

At the patch panel end, Do I connect it to the chassis of the patch
panel or do I have to use STP Cat 6 sockets that have a ninth terminal
for this drain wire?

Stephen