Remember that story recently that said that the Russians might cut the undersea internet cables ?
It seems the story/scenario was concocted because someone had noticed a Russian spy ship that has known cable tampering technology and a mini sub on board was on the move from its normal location, the story sounded a bit over the top at the time and now it seems was simply 99% hyperbole or horse manure in simpler language.
Theres some data here regarding the ship and where it is atm, I think we can all agree that whilst a lot of things "may" happen in this world, some events are too inane for the real world. I wish the mini submariners good luck in their current hunt.http://www.bbc.co.uk/news/world-europe-42543712
The normal method of intercepting undersea cable traffic is to actually cut into the cable and run a tap from it and disguise the few days outage by talking about a ship dragging its anchor etc, a simple cover stoy and one that allows for the time to do the splicing.