perlroth, security reporter for the new york times will. she joins me now. quickly on the currency here. cryptocurrency is being used for this. there's always a joke about it, it's like a currency in search of a use case. this seems to be a use case which seems kind of problematic. i don't have strong apart pinion's either way. >> yeah, cryptocurrencies have really field ransomware attacks. there's no question about it. ten years ago when i was covering ransomware attacks, they were charging people $200 and they would tell them to go by a prepaid debit card and handover the pin to it. now we're seeing them use bitcoin and more narrow, which is an ominous cryptocurrency. one of the things been discuss right now is why don't governments in force, know that customer rules on the crust of cryptocurrency exchanges. unless we get this car problem