Risks in the global payments and settlement systems.

There are some lovely little new systems which have well and truly taken that into account. In fact it has to be the foundation of any architecture. Robust, proven '5 nines' technology and equipment and decentralised. 

At the end ot the day...when you settle - so long as you can. 

So long as you can see what your exposure is you're ok. Of course it is lower risk to settle instantly, but it may be more cost effective to do it periodically. The essential thing is to always know your exposure and be able to take a snapshot of it at any time - particularly if some system somewhere goes down. Ideally it should take an incident which takes everything down to take you down and your exposure is at least not increased while you are blind like everyone else. There is of course the option of 'invisible' systems which aren't able to be seen and an attacker won't know where to look to take them down. Mechanical failure is able to be catered for, it's really only the attacker type stuff which isn't. I'm all for a bit of stealth myself.

It certainly is an argument for instant settlement, at least your risk is contained if the lights go out.