Could We Ban Encryption? - Computerphile

Key Takeaways

well you can't realistically ban encryption because it's the DCT Tech that holds online systems together um it's how you protect your Communications from your browser on your laptop or on your mobile phone to your bank or to a shop where you're shopping it's not just that if you use a prepayment electricity meter for example and you put in a 20-digit magic number when you've gone and bought 20 quids worth of more uh juice then that's cryptography that is enabling you to take that transaction from the shop where you spent the money to the meter where you're going to burn the electricity it's used in hundreds and hundreds of different ways to just hold hold things together encryption we've got politicians at the moment saying we need to get rid of it or be able to be read by our security services or whatever what's the reality of of how that could work or what would happen the reality is that a little bit over 20 years ago there was another attempt to ban cryptography because just after Bill Clinton get elected president of the USA the NS went in to see him and they made the sales pitch that he should bring in key escroll the duty on everybody who uses cryptography to give a copy of the cryptographic key to the NSA and they tried to introduce something called the Clipper chip which had a government backdoor key baked into it but a friend of mine Matt blae brought the Clipper chip which caused Great embarrassment and humiliation to the NSA so they can back with other proposals one they had in Britain U was that we should have to use trusted third parties and that if you're going to use cryptography you would have to have the key certified by someone like you know verisign or Barkley's bank or um BT who would keep a spare copy for the cops in case it was needed to decrit your stuff and we had all sorts of fights about this for example just after Tony Blair got elected he went back on a pre-election promise he promised that he wouldn't ban cryptography and then algor went and talked to him and he changed his mind and so what we did in a hurry was to print the Thousand or so most important cryptographic keys on the internet into a book and I've got a copy here and this is the global internet trust register so we went to see Chris Smith who was the culture secretary and we said Chris your government's about to ban books it's about to ban my book here and we showed them all the cryptographic key material in it we said you're the minister for books what are you going to do about this that at least got it on to the agenda of the cabinet meeting and it didn't just go through on the and there was a huge big Row in kafuffle and it eventually get handed off by DTI who' been pushing it to the home office who were prepared to push it a bit more brutally and it ended up becoming the regulation of investigatory poers uh two act 2000 and in the end all the ACT requires in respect of cryptography is that if the police want to decrypt something um and they believe that you've got the key for it then a chief Constable can sign an order for you to do that decryption and um this was where we thought we had um you know got an agreement on how cryptography and policemen could live happily together now all of a sudden uh the cops are back and they're asking for more so just just to remind me again so that was 20 years ago that was that's right how do they go 20 years and think okay right hang on we'll have another crack at this I wonder I think what's happening in the USA is that FBI director James KY wants to scare apple and Facebook to not use cryptography uh as pervasively and as competently as they do in products like what's Happ in FaceTime um here in Britain I think that David Cameron's just jumping on the bandwagon and he's adopting this in order to look tough and Strat and um appear to be tough and Terror and tough on the causes of Terror uh but in reality um a law like this isn't going to happen because it would have to happen in America for it to have any effect and Congress in America can't make laws at the moment so it's BAS basically Bluff and Bluster and posturing between um American Tech Titans on the one hand and American intelligence agencies on the other all of them seem to be forgetting that even the most mundane of transactions relies on this encryption so it's not just a matter of um transactions relying on encryption in many cases the tech Majors have brought in encryption in order to avoid the problems that are being caused by law enforcement itself now if you're Google one of the big problem problems you face um is that a family court in India um may serve you an order telling you to hand over the Gmail of somebody in Canada who's never been to India and putting on a lifetime secrecy order now how can you simultaneously give believable assurances of privacy to your users in Canada and also employ engineers in India well um what the big firms do at the moment is they just insist that their lawyers in California are involved in approving every single decision to hand over stuff to law enforcement agencies and the police really don't like that the police in Britain for example really don't like the fact that they've got to phone up Facebook's call center of their abuse team in Ireland and say please in order to get access to stuff they would rather be able to serve warrants and tell people to shut up and just hand it over but that's not going to happen in a globalized world you can't have a world where 200 odd countries police forces can all have surreptitious access access your stuff without you ever hearing about it so if you're a tech major how do you deal with this well quite simply you encrypt the traffic end to end and that means that if MI5 comes up with a warrant or the Russian secret police or the Chinese people's Security Police or whatever and they say hand over Ross Anderson stuff um then Facebook or Apple or Google can just shrug and say search us we don't have it that's a cipher text it's only the end points of the key this episode of computer file was brought to you by Squarespace you can start building your website today at squarespace.com if you enter the offer code computer file you'll get 10% off their plans start at $8 a month and if you sign up for a year you'll get a free domain so start your free trial today at squarespace.com you don't even need to put in your credit card details and if you're a real computer file you might want to check out the developers platform developers. squarespace.com just remember that code computer file for 10% off you want to send me a message I don't have to share anything with you you just know my public key encrypt something with my public key send it to me you know I can decrypt it