Trying to get to grips with what is what with the BT cables coming into the house. I've attached some pictures 1. BT Cables outside of house Here you can see two cables coming to the house. One goes down towards the front door and the other tracks alongside first storey of the house and seems to wind its way through the rooms to the box room. Question: Does the fact there are two cables mean the property had two separate telephone lines? 2. Master socket in entrance hall The cable that runs from the front of the house towards the front door (let's say cable A) comes into the hall into what looks like a master socket given the relay and capacitor. However, it seems then to be linked back directly to another cable which goes back out the same way. Question: Is this a master socket? It doesn't appear to have the double plate thingy where by you can separate all of your internal wiring from BT's. 3. Connection block in bedroom The other cable coming to the front of the house (let's call it B), after running along the first storey external wall comes inside the house and is joined in this box. Question: I presume that this is some sort of terminal connection box? Can I mess with it? 4. Another master socket. That cable B then ends up here in what looks like another master socket in the box room. If I am correct about their being two lines, this would appear to be the 1st master socket for cable B. Question: If I am correct, I guess I can't touch this socket and it's owned by open reach despite it being deep inside the house? 5. Bedroom master socket This socket appears to originate from cable A. After it goes into the what I presume is a master socket in the entrance hall, it comes back out of the house, around the house and terminates in this box which does look like a master socket. Question: Is this a master socket? It looks like one and has the detachable part to remove my wiring from BT's. To my untrained eye I seem to have a lot of master sockets! Would welcome some opinions on what I have and what I can get rid of.