He's only providing a lower bound for this numbers, he specifically spells your concerns. He mentions that any improvement on: * number of cores per CPU * num

He's only providing a lower bound for this numbers, he specifically spells your concerns. He mentions that any improvement on: * number of cores per CPU * number of CPUs per server * any improvements in cryptanalysis * instruction set improvements (arm sha1, gpus) Will only make his number even scarier.