“Rather than hacking into an individual bank, the assailants might aim straight at the heart of global finance by choosing as their target parts of its essential ‘financial-market infrastructure’ (FMI), such as clearing houses or payments systems. FMIs are like the plumbing in a city: they facilitate the smooth flow of money. Because plenty can go wrong between the promise of a payment (eg, writing a cheque or making a digital purchase) and its actual settlement (the money arriving into the bank account of the seller), clearing houses sit in the middle of transactions to process them and insulate both sides against credit risk.”
Source: Joker in the pack