This sudden surge of requests, which were cancellations for a large batch of orders that the machine had never actually sent out, acted like a denial-of-service attack on some parts of the New York Stock Exchange.
That machine routinely processes 70, 000 orders, cancellations and trades per second but can handle up to 250, 000 per second--enough to deal with trades on the Nasdaq plus the London and Paris stock exchanges with room to spare.
As the ambush intensified, Sgt Meyer defied his commanding officers' orders to jump into an armoured Humvee with a fellow Marine and brave an inferno of machine-gun fire, bullets, grenades and mortars.