Wait for it now. We'll be a good time to remind everyone that there will be language in this show this evening All right, welcome everybody All right, how many of you this is your your first bad voltage live? What shows this a bad voltage live first show all right. What about the people you're here last year? All right, you people need to show the new people how things work, so we're gonna practice a little bit All right, you guys ready for this all right, so I Do All right, so the more passion the more energy you guys put into this room The better and worse these four gentlemen will be so it's really up to you I mean we've got a whole captive live audience on the internet something like seven and a half listeners Gonna be listening to this live podcast tonight, so We need to make sure that you guys are pumped up Get your beer man.  I'm sorry. Sorry. All right, so we'll practice here Left side of the room. Let me hit right side of the room. Let me hit All right good. Okay volume control you guys ready? Yes. That's what I'm talking about All right, so see you guys are Linux people. We obviously can't do anything without fricking explaining things over and over again So So we got some ground rules and stuff that we're gonna set but first things first I like to introduce Ilana rabbi vanovic in Lutahosen Get up here get up here One more time. I knew you guys could read documentation man. Someone owes me some money All right, so you guys ready for this Give me a little bit All right, what you've all been waiting for four of the dumbest technical critics on the internet everyone has ever known and generally speaking Horrible horrible human beings you've been waiting all week for this give it up for better John O'Bacon Stuart language Charlie Garcia and the other guy Start What's going on here? Okay, what do you think? Let's see if this actually works hang on Sound guys, can you come and try and fix this for us? All right, the sound guys are fixing stuff. Can I get house lights for two seconds? Yeah, and some problems there is there is anyone back there. Oh, you're the house. Yeah, never mind but It's everyone have a beer or something like that. That was a sore subject, wasn't it? Ah crap It seems to be when it's so what I like to do whenever I start to show is make sure that nobody gets drinks And the sound doesn't work So it's gonna rock out pretty hardcore. We're two for two so far. So thank you very much Let's let's see if we can take a picture in the dark. Yes We're taking a picture. We totally can do this All right, all right. Well, these guys are working on that and we're ignoring the operating system on the screen behind us Jesus Christ, it's amazing the photo background pictures look like these days Take your issues over the Libra office team Everybody Everybody prepare whatever face or hand gesture you would like to make to the entire Internet We'll give another show a started. I'm assuming it's gonna be all middle fingers That guy should think so well, there are Well, let's get this let's get this and and each one well deserved. Okay guys. Here's the thing. Here's the thing Here's a good answer for a second.  It's blurry I'm trying to do you a favor so you don't just look like you're waving to me angrily Once again, if you would like to give the internet the bird keep it still Beautiful just beautiful Hey, he did that on purpose at that time. So Shit Now try See this is why I don't prepare for anything. There's never slides to break You just you just wing it and it's fine somewhere. I'm just young is crying his eyes out At least we're live streaming this yeah, I'm switching off and on again people No, this is not the entertainer we were expecting to deliver No, take a little bit more time because I've never been flipped off by 700 people at once before I'm gonna tweet that All right bear with us entertaining the London I'm tweeting right now. Joe. I'm very busy Well, that's that's actually pretty good. That is that is a lot of Look at that. Hey, that's excellent right so it concludes our show. Yeah, thank you very much It was lovely now the after party Stuart what is the proper caption for a room full of people flipping you off? Just another bad voltage life Whitney I've been living my life a long time.  This is good Nobody wants to see that We have requests for stripping. I see no one's talking to Jeremy rather than me Fair fair some shit, but it was kind of go get stuck in Well, he did have no shirt on last year. So okay now Hang on. All right, this is exactly so right about now is when we're going to have an impromptu Q&A session Yes, absolutely. Does anyone have a totally awesome question to ask? How old am I? It's a really boring question you Shown those Mac like a potato That's a really good question Why are there not any women on bad voltage live?  What's your name? Tonya, could you be Tonya really quick? Yeah, I have power You have a PhD in chemistry I Went to college to get a two-year degree and I kid you not visual basic programming. I dropped out so This explains a lot about Sosa Ah Quiet bomber Okay, I'm sorry. Yes. Do we have other questions?  We've all been running the show in windows and realistically we can't have a go at people at this point It's the worst beginning to any show in the history of mankind This is not the beginning I envisioned.  Don't treat me chemistry girl. Let me sit with you guys Hey, how are you doing? I'm doing fine. How about you? I'm doing all right. I guess These guys are exciting What's your name? Mark your name is mark. Yeah, you from around here mark. I'm gonna need from around here That was fantastic. Yeah, okay. That's all this off the small talk. I got for this right now. John. Oh, are you done yet? No, we're getting there. I'm moving again. Maybe again fun. Someone else To talk you Available is there a sound engineer available? We have it up there next to John. Oh him up there I just called him in it. He's gonna hate me now So, I guess we should take this time to try calling tech is an after-party and there will be more free beer Everybody quiet for a second quiet for a second Jeremy, would you like to talk to them about something? I just didn't did you just tell them about it? What hold on hold on everyone quiet for a second quiet quiet not joking We have we have you can stand it's fine Tonight after the show Can you guys can you guys hear me now? No So after this at some point in the dim and distant future in the show finish We have an after-party We're gonna After the show finishes and there will be free beer We know you guys all deserve very much I don't I believe it's just yeah, I think it's just beer. I believe you can buy Hard liquor if you want to but speaking as a beer drinker. I'm fine here. It's on there now. Look. It's elementary. Oh, yes This time crush your fingers. This is the worst thing ever Yeah, Mac just works Bring it.  It doesn't work now So first of all, thank you to Linode give them a massive round of applause. Yes huge and Microsoft Thank you to Pogo Linux to win this thing down here Yeah I Thank you for sponsoring off the party to take your master All right, so please we have no audio whatsoever, so this is gonna be interesting Yeah, this is gonna be interesting particularly for a bit later on. So why don't you you too right run away come on So We're gonna start our first segment here I've known him Stuart language now for about 14 or 15 years This is when you go oh I know it sucks He used to be a really hardcore free software person when I met him we We'd argue for hours about free software on Skype and um Which is illustrative of the point and anyway, he was he was always randomly waving about free software and over the years He's become different. He uses a lot of non-free software has gotten iPhone at least used to have an iPhone Um, and he considers that to be his enlightenment I on the other hand have not known him for 15 years, but I do know some details about him He used to work at Microsoft professionally developed software for a Mac. He was a fairly hardcore proprietary guy. Yeah, it was Now he won't even use a phone because he can't find one with a free baseband So he has made nearly the opposite Transition really that ac has and that's where his enlightenment is We personally think that one of these two people is right in terms of the enlightenment Or we want you lovely people to decide so we're going to have each of them get up For a few seconds to share their story and then we're going to have a bit of a vote at the end of this All right, so first of all, welcome to the stage mr. Language right so My journey to enlightenment and the comparison with Brian's Journey to non enlightenment, right? I used to be Super hardcore free software. That's him by the way I had no Wi-Fi on my laptop because there weren't free Wi-Fi drivers I didn't have mp3s to listen to because mp3s are non free.  No computer. No compromise. No hope at all Now let's be clear here. I'm an I'm an Ubuntu user. I'm not for example a Mac or sex user I work for myself and all my work is done on Linux machines I'm not stressing when we have to Windows 10 or whatever But the important point is that I'm sure Brian is going to kind of on stage And he's going to do a terribly rousing thing about how you should embrace a free software lifestyle And you'll all agree with him, right? Because it seems like the right thing to do when people stand up on stage Places like scale and talk about how you really ought to be using open source software and not the Mac or whatever You'll think yes, totally the right thing to do But will you actually go home and do it? No How many of you Gmail users? Right when someone tells you you should be using only free software stuff And you should move away from Google services. Are you going to delete your Gmail account?   I like being able to take photos on my phone Plug that into my computer Brian has pointed out hasn't got a phone Because as far as I can tell loving free software to that depth means you have to revert to the middle ages It's it's done an enormously good job. He's cut the cord right moved away from Google services Stopped using proprietary things. That's great right, but If you want to do the same thing if you want to stop using YouTube you want to stop playing games You want to stop talking to your family Read his articles Follow his example Right If you don't want that if what you want actual enlightenment then what you want to do Is vote for me a fairly compelling argument I would say The only thing I liked about that is that it sounds like it's losing his voice Yes, it's right What do you think what do you think compelling? The crowd does not seem convinced I think that was a courtesy clap All right Why don't we bring up to the stage? Why don't we think about bringing up to the stage mr. London? Did did I just make an audio start to work all of a sudden? Yeah, we changed that I did that Can I have my slide please? No Bad Stuart bad Can I have house lights, please?  You're not on the side right now. I'm in the middle. All right Yeah, yeah, yeah a little more I wonder if the lights aren't working Just take the picture really really quickly Okay Could everyone act like I don't know you're a referee and you just declared a touchdown Everybody there it is touchdown That was really beautiful And you guys did that for me and uh, hold on Stuart had his time. I have mine Where's the twitter button tweet? Not screwing around on this everyone This would have won a lot quicker if you understand that freeze Stuart Is just what this audience wants is Hashtag skill 14x There we go. We now have definitive evidence That you were incredibly wrong steward language Right there right there. That's your argument and It's an open source phone running android running linux. It's not a phone. It's camera I was going to say by phone you mean completely utterly not a phone. It looks like a phone But it's just a camera it runs and it's fine and it's totally reasonable to be a completely free software household The man makes a fair point Drop bike rock off stage. Do you want my job? Whoever it was who sent that? That was great That man made a really good point Twitter Yeah, but steward is still wrong All right. What did you think of him? I'm on So there's an important detail we've left out of this god damn it So last year That wasn't a quite important detail actually so last year we when we did live voltage here We had a punishment in the quiz that we did where we some of you may remember We took some electrical tape and applied it to the loser's arm and ripped the tape off It's not as good as it sounds When we did that we thought what we're going to do for a punishment this year We thought electrical tape isn't going far enough. So we've gone full on beat waxing strips now I will see when we came up with this idea steward and brian were not as happy as you guys are I can't tell you the weird looks that we got when him and I went to buy beat waxing strips together at a safe way So most of us were like no, we really need the big ones So I'd like to just say that when thinking about which way you want to vote Maybe don't think so much about free versus non-free.  I'm happy to say I have no idea Do you want to take at all do you want to take care of again everyone to vote now? Whichever one of us loses this is going to hurt a lot All right, so we're just going to do this by a basic uh noise ometer. Oh really? Okay, now cool go for it. Yeah, I know I want I kind of want this to be able to be recounted, you know At the after party we'll wax the other one So if you think mr. Langridge made the most compelling argument or you'd like to see him get waxed however, you would like Hang on Which is it? I can't I can't either win the thing Or I said please you're every fucker votes for me That's no good All right, let's see who has the most compelling argument Do you agree with the one with the lowest level of screaming is getting waxed to think about that way? So mr. Langridge thoughts And now mr. Landuk Actually closer than I anticipated it would be shit It was it was very nearly a draw I think if nothing else we owe it to this crowd to see both of you get waxed All right, so so in a draw Jeremy and Jono get waxed, right? At this point, they're just going to yell for anything Which of my arms do I need least? Oh my god If you're going to do it do it right Are you going to have audience members do it? Do you want to come up and do this one? They're inviting experts onto this Let's count down. You ready amazing after three three two one He's earlier than him.  I want science princess to do it. Oh science princess is going to do this.  That's not how it works. Ready three two one Oh I just like to say that this is hilarious Think ever why do people do this? Fucking we will be auctioning those away later at the after party That was more satisfying than the birth of my child Okay, so why don't we uh, why don't we do more than 60 seconds? So Oh, this crappy show is so not worth what I just did Yes, so now we have explain wrong in 60 seconds How many of you were at scale last year and saw bad voltage live? All right All right, we do think we called it wrong in 60 seconds And the deal is that people come up on stage And rant about something they hate And then we all vote as to who did the best But we shouldn't really be the ones to explain it Where is it? I think we could find a better way to explain it last year. There was a guy who blew the doors down Step up Chris come on Those of you who were here last year will remember Chris making an emeritus second appearance on Chris came up on stage and Knocked the roof out of the building with the power of rant. I've never seen anything like it so You've got 30 seconds or so to explain to these people How to do it right All right, uh, how to do it right there I think the most important thing is to think about what rage and a rant really is And who we're working with Jerry Seinfeld doesn't do rants. Okay, Howard Beal does rants We want nerd rage We want the kind of frustration that doesn't come from the terrible things happening in the world Like people dying and wars and pestilence We want things like emacs versus vi type safe languages versus Duck type languages I want to hear about the importance of bsd versus linux.  Thank you guys and I should I should point out here He he won last year in la and he was hilarious We did this in fulva at the last live show that we did and a guy I'm not kidding you screamed on the top of his lungs for 60 full seconds in german about jono Was epic. So the bias the bar is set very high And consummate with that high bar is a very nice prize. Do you remember the second guy? The second guy in fulva threw his shoes at the audience Yes, you did. Don't do that. Don't do that. We don't want to get sued Don't do that. You should talk about the prize because it's not just for the satisfaction of laying into Your choice of hated ubuntu thing. Look at that This is our prize Thank you pogo linux. You're not for pogo linux. So look at this Give it up for pogo So for those of you who who can't read this, this is an intel quokka i7. It's 16 gig of ram It's a beast 480 gigabyte satin disk. It's got a six terabyte satin disk GTX 960 this thing This thing is going to become skynet if you let it, okay So this is very ad hoc. We're gonna want some people who pick a topic Now it can't be hateful. No racism sexism any of that nonsense Okay, something that you can run about for 60 seconds. Who wants to do this? Hands up. Hands up who wants to do this? Hold on. What do you want to talk about? Hold on the guy in the super amazing outfit. I don't want to be up Okay, I'll hold on Okay, barn pick a guy. All right. What's your topic son printers? Just in general Printers get up there Printers I want to see what he writes about printers. What do you got now? Wait, wait, wait, let's get John to get one This guy that guy All right, how do we got one over here? Macbooks at linux event at linux conferences Macbooks at linux conferences. I like that one Running around with a sub up to the conferences any volunteers This guy Linux desktop environments linux desktop environments Huh? No, I got one over here. I got one here Why does amazon hate linux? Why does amazon hate linux? That's a question. That's not a rant I hate amazon. Why do they not work on linux?  It's worse than you think Yep audience likes it seems deliciously abstract No j s and why you'd want it on the server That guy like that Oh, Matthew Garrett I would love 60 seconds to complain about people who claim to represent this community while standing on stage Basing everything on proprietary software and failing to sell free software. Yes Matthew Garrett come on up I believe the crowd has spoken. Thank you, man. So we have our three All right, we've got our three off inside So hang on so we're voting Matt go on stage to give us a bollocking and then we might give him a prize Everyone's like, yes Okay, so should we bring the first person on come up? What's your name? Brian Brian Smith. What are you dressed as I'm a geek. Oh, okay The geek. Oh, did you put him up at the middle of the stage? Okay. All right.  Where's the countdown? It's about to appear. Okay. Okay We have no music can we put the music up people a bit louder if you can Yeah Okay, if you think about the one thing that has never worked It is printers the only time anybody ever uses a printer is because there is some out-of-date company that decides Hey, why don't you mail this to me because we're not actually smart enough to set up a good system So you can even email it. I mean come on Just let me either use an api or email it or just I'd rather write something on a piece of paper with a pen And stick it to a carrier pigeon and send it to you then have to deal with PDFs and printers And printer drivers and trying to network something with a printer because somebody is still stuck in the paper age It doesn't matter where you are. What system you're running It is worse than anything if you have to print something It is just you've already failed for every you are prospective ever One printer There's no bandsmith Next contestant, please step To the stage take your microphone. Something really weird about seeing someone in that outfit ranting like that about something Beautiful. What's your name and what are you about to talk about? Deb Nicholson Video on linux and amazon Okay, are you ready deb? Yeah, wait for the countdown You ready for deb? Okay, here we go Let's go. Okay. So if you like free software and you're running a linux or a new linux system And you want to watch you want to watch video you have like not that many options Because netflix is terrible. You have to download their stuff and then you get all the dm So when you're like, okay, I'll get my towing on the amazon I already got to use them to get all the stuff for people for christmas anyway So you get that you're like, I'll just go to their website. They're like, yeah Oh, we changed our video codex again in the morning yesterday Why because that's what we do we're amazon we could totally just do that anytime we like you go there Every single time their forums like you know a whole bunch of us and and I know we're sad We feel bad about it and we post we're like we're leaving you because you aren't supporting video on linux anymore You jerks, but we come back because what are your other options? You have to do it one or the other So you go out you're oh, hey, honey watch a video It's fun That's over Give it up a dub All right next up we've got the internet's matthew garret Okay, are you ready? Hey, I just like to say design matthew garret's intellectual design proponent and anthropogenic climate change denier Okay, dr. Matthew Garret, what will you be running about? You Get ready Let's go We are standing here as a conference devoted to the most triumphant piece of free software that has ever been produced by humans We are here because we have used free software to make our lives better And here we are on stage with someone who decided that keynotes was better than libra office We are here with people who are so poor at freedom that they can't even get free beer to people in a tightly manner I am sharing the stage except i'm not because he's wandered off with someone who thinks that twitter is free software Are these the men who you want to be our face to the world? my friends Thank you And All right, so we're gonna do it take technically we have to vote Yeah, we should we should we should wow the geekle man What do you think give it up? How about dab Give it up a dab If you hate video on limits All right, i'm not looking i'm not liking how this is going close your eyes How about Matthew Garrett? All right, sounds like we have another tie The only thing good about this is i'm not sure if we can lift the box Matthew that's over that big box over there. It's yours Thank you to Pogo Linux for sponsoring wrong in 30 seconds Pogo Linux the all fantastic excellent workstation from our garratt Presumably secure boot will work on it soon All right Feel the center of this do you want to maybe was this your idea? We have a discussion there was a yes, this is actually a discussion there was An interesting thing came out of a few talks that i've seen here at scale over the last couple of days that An awful lot of the people in this room are kind of We're in our late 30s or 40s or older and we've been using Linux 15 years 20 years and that's great But it's not hugely clear Where the next generation is coming from now that there are plenty of exceptions You look at kilo banks came up stood on stage did an excellent job talking about the future of Linux. That's fantastic But there aren't that many people here and those of you who have prepared to declare your age. How many of you are under 25?   Like five six princess chemistry. I mean that's not a whole lot of us, right? So what that what that means is the vast majority of people here have been diehards for a decade literally some of you since Well diehard 2 was actually produced that's kind of amazing So where does the next generation come from not just young people not just 12 year olds But like the next round of people coming into linux I kind of tired this to age that wasn't necessarily right because we want to get just as many 55 year olds as we do 15 year olds Right, it's about the I say more. We're looking at you. I think we need an army of 55 year olds Just marching down the street proclaiming free software. I think that's the right market for us But but this is one of the things where we're interested in your opinion to some extent, right? Um, yeah That sounded a bit more dismissive than it was intended to shocked but Who's got thoughts? I mean, maybe some of you think no, it's just not a problem There are hundreds and thousands of new people coming into actually can we get a show of hands? Who does think this is a problem raise your hand if you think it is an issue should we be getting more new blood? So not as many people as out of ante Put your hand up if you think it's not a problem If you ask it again, it's kind of evenly divided each second slater Well, let's start with this right somebody who is brand so you're brand new. Yeah, okay How did you get how did you learn about linux? How did you learn about? Okay, um, so my brother-in-law always talks a lot about how everything should be open source and awesome I've been seeing how well that works for him in his everyday life because all of his phones and his computers always work all the time That guy jason. All right jason. All right jason good work jason jason. So you're bringing people into linux, right? I I try That's it. How's that guys? But how so distrust are like drugs Wow, I'm not sure where to go with that one. So Uh, I guess I'm curious to know, you know, because I mean we're all kind of old farts up here like how Did people get started in the last couple of years because I mean I got started through a linux user group, but What about this chap here? Um, just yell it out and we'll repeat it. Just shout it out. We'll repeat it Wait, who okay, so you're eight or nine years old and someone hands you a book about a bunty. Who who handed you that book? Just like some weird guy in a van. Yeah Hey kid, have you heard about the distro for humans? It was not a guy in a trench. No, but seriously who and who gave you the book? Who gave you the book?  I don't care why you like it. I wanted to one more thing though. What got you to that hacker space? In seven words or less Your parents so that's cool parents are great by the way. Yeah Hey parents are you parents here? Is that your dad? Wait dad good job dad Who else there were people over here had their hand up for being into linux for less than a year Who else is recently going to learn? Is someone there right at the back? Someone's pretty stoked about it back there. I'm gonna go run Run Is that you? Who is it? Who am I going for this guy? Yeah, it's you So I've been using linux for past like six months. I had like basically, um, I'm a part of a program Programming guild and then basically, um, I've been I was using microsoft for the For a long time in my life gaming and everything and then my mentor loves Loves calling people that use microsoft macrosurfs so So basically Yeah, so basically from for me like I had to learn the hard way using putty and all that other bullshit Make him to win scp and all that Like I installed gentoo from as like my first my first linux to show and Yeah That that was an experience. I didn't So to be clear he got into linux through peer pressure All right, is that is that some of that back? Pretty well. It really is a drug, isn't it? Yeah, I I hated I hated coding on windows Yeah All right, so one more person one more. Yeah, who's new to who hasn't said just yeah them Someone who's you hang on. We got someone New person down here. Okay. What's your name? Andy So my parents decided that I should have parental controls on my windows computer because I was using my computer too much And uh, I was like, yeah, I'll just get this linux thing that I've heard people talk about So I got an ubuntu live disk and that that it's it's a gateway drug. Wait a minute.  We know what you're thinking Okay, I won't say it Everyone thinking your head when I was about to say It's good, right All right, so there's kind of a theme there, right? It's people wanting to go beyond boundaries that have been set on them Yes, I think so doesn't seem like a thing that's coming through How many of you would say that you you got into linux because you found yourself Unfairly stopped by whatever you were using before That's a lot of you. That's a lot of you. Yeah, can I see one more question as a show of hands? How much is conferences not just scale? We all love scale. That's brilliant But other conferences how much has this played a role in your interest in linux and open source? Put your hands up if it has played a significant impact Huh, that's like over a quarter of you. Yeah Interesting Getting into it. I think getting into it. I think getting into it is the most important This is the point we're talking about how we get the next generation the next wave of people in here The people who are going to be at scale in 15 years, you know at scale 29x or whatever you see it feels to me like I'm sorry by the people who be at scale at 29x will be you know us It's going to be Elan and Leda Hosen again. It is So seems to me So seems to me like a key thing here is thinking about what are the It seems like there's a set of human instincts that is just interesting Like I've met a lot of people who got into linux and open source who are A little subversive or they're really technically curious and you know what they had like the Fell at the back about you know windows wasn't very interesting as a programming environment and I wonder how we expose What we've got to those groups That came out wrong And you're all dirty Yeah, I think I think we should move on I really think we should move on let's move on all right important that we move on all right This is going to be interesting with all the AV problems that we had All right, roadies. Can you come in and give us a hand? Yeah, thank you roadies. Okay roadies, but they're going to take care of the stage right here So um take the chairs down. They're going to sort they're going to sort the stage out for us Meanwhile, we're going to describe What this is what this is All right, how many of you have seen a tv program called family feud? Just for my own personal english satisfaction. No, how many of you have seen tv program called family fortunes Matt garrom It's time show just in england. Um, so this is family feud Right and the important thing from your point of view here is There are prizes Let's talk about the prizes. All right, so excitingly How many of you filled in the survey that we sent out? All right, so you people with your hands up could win prizes the rest of you you should read your emails from scale by the way So So what's happening here is we've got a set of prizes. We sent this survey out with I think it was four questions Uh about four questions and then you could answer those questions And we had over a hundred people fill in these the this survey We also asked for each question Why you wrote what you wrote and we thought the funniest answer should win a prize So I want to show the prizes first of all you can win one of these These are raspberry pi 2s the raspberry pi 2 These prizes by the way occur to see of the sponsorship from linode and microsoft. So the raspberry pi 2 kit, which is pretty cool Um A retro mega drive games console Sega Genesis for our american friends here Yeah With 80 games Sonic the hedgehog bottle combat. All right An amazon fire stick Yeah Oh shut up um Jesus Yes, it can do All right, and uh, and then finally you won't get one of these tonight because it's not been it's not in production yet But the mycroft ai that everyone's loving Give it up for the mycroft Yeah Okay, so uh, so this is what we've got available now We can't really do this ourselves. We really need a quiz master. We do we do So we think it is the best person to bring out to run a fantastic quiz A family feud quiz and there is Only really one person. He's got a A very squared jaw line. He's the tallest man in open source He's so dreamy put your hands together for gareth greenaway There it is Their jacket looks as fly on you as I hoped it would All right, take your take your microphone All right, all right full I don't know where he's going. Uh, oh he's getting this thing. All right. So um, so we're gonna uh, well, let's just hand over to gareth You explain let's do it. We're gonna hand you over to gareth All right, so as jonah said, we're gonna play a little game of family feud We have one highly dysfunctional family here already But we need the second one. So I'd like to introduce Our second family Second family come on out Oh, or not Second family All right, put him over there put him over there. Yeah careful walking over there This is a surprise An alarming surprise. All right. That's disturbing. We've already met these jokers. So our second family. We have root sealy Yeah, give it up We have mark hinkle We have mr. George castro And under the potato sack we have Matthew Garrett All right, so this is gonna work just like family feud does Each team is going to we're gonna play each round each One will have questions. They're gonna give the answers Etc. All right, so let's have our first contestants to the front of the podium. Let's play the feud Let's play the feud Yeah, god All right, buzz in when you think you have the answer Wait, wait, wait, where do we keep our hands? Is this cool? No, right there. You keep your hands right there All right. So first question according to the scale community What is their favorite linux distribution root What the hell?  That was awesome Do your whole thing like that. That was a brian impression with a really deep voice Right, right. I'm not really the sort of person who would stand here and swear to use only free software And then are you gonna answer the question or what? Well, the problem I have is that I feel Don't explain it answer the question woman Brian, brian, I take it you have never seen root as black widow I have not Tread carefully my friend tread carefully Ruth favorite linux distribution I just wanted to say that I felt contractually obligated by my employment to say other things But for the sake of winning I'm gonna say that the crowd probably went with ubuntu It's a bold move. It's a very bold move Ubuntu says All right, root root. Would your team like to play or would you like to pass? We can smoke. We're gonna play. We're gonna play. All right mark Same question according to the scale community. What was their favorite linux distribution? fedora fedora Survey says fedora George they're starting off well George same question. Well, they'll tell you every time you ask so arch Let's see I don't know arch linux survey says All right, Matthew So can I just quickly ask for clarification whether we're talking about linux or gnu slash linux?  There are three more answers I guess now's the part where I say optimistically for my employer red hat enterprise linux Do we have red hat enterprise linux? Mark three more questions one big x Can I get a mint? Can we get a mint linux? psych Brian probably cheated so I'll say open susa open susay Matthew At this point. Can we give it back to them? You got two x's Matthew If you answer one if you answer if you want to answer an incorrect answer on purpose it'll go back to them I also have contractual obligations, but I feel that they're really not going to work out well here so um Everybody we know come on these people have done so much for free software We know that you guys and women. I'm sorry. That was careless of me We know that you love oracle unbreakable linux Oracle unbreakable linux survey says So matthew clearly thinks we're incapable of getting one answer clearly what that means All right, we get so we got a lot of pressure on this. Can I confer or do I You can confer What do you think?  I'm going centos centos Centos survey says Oh, there it is. Centos. Okay. With the steel Excerpt me. Very nice. One more answer. No, no, no, we get one. We win. We win. We get one, we win. All right. All right. The winner is a round one or the bad voltage family? Sorry, we still have all our hair All right, so in preparation for this game I was asked to review the answers as well as the comments that justified them It deeply changed me profoundly There were some very disturbing things in there very disturbing mostly about brian londuke Zero surprise, um, but I picked some I picked some answers Based on people that said that they would be in attendance ones that I considered funny And they have the the possibility of winning a prize so One of the the linux distributions keyword linux distributions that someone said Was their favorite? Was open bsd And the reason that they used to justify the answer Was they really liked the puffy fish Oh, and security is good, too So is mike Shroful here? No, okay I'm not surprised So the the other one that I noticed, um, that just kind of jumped out at me was The answer it was short and sweet and to the point it was debbie And the justification was To really annoy and make george castrow cry And that was bill chilleders is bill here Yeah Come on up come on up and claim your prize Come up Bill you have the option to select one of these fine prizes Red bill is taking the raspberry. Yeah, good choice my friend congratulations bill. All right round two Oh, what was the last one? Yeah, what was the last one? What was the last one? Oh last one? Let's reveal the last answer. Sorry fried chicken Fried chicken That makes sense I will I will be I will consider it a personal insult I will be deeply disturbed and disappointed if by the end of scale there is not a linux distribution Named fried chicken. It's already compiling Okay All right round two. All right Mark jeremy Gareth please fill in the blank What would you name the next? Ubuntu release Jeremy yuckity yuck You sure about that? I'm confident my answer. Yeah, you feel you feel pretty good. Yeah. Yeah. Yes So do you want to pass or do you want to take it? We want to pause pause this question We would like to pass the bad voltage family is going to pass Are you serious? Apparently apparently thank you for for google searching that I assume So taking the time There is a linux distribution called fried chicken That's awesome highly disturbed the mine reels Mark Same question. What would you name? What would be what would be linux community the scale linux community? Call the next ubuntu release It starts with a y I have to go with yellow pad yellow pad yellow yellow Yellow survey says Mark George I'm gonna go old school and say igrecil Igrecil Do we have igrecil? Would have been hilarious I'm sorry. I have no plausible way of getting this right. So instead I'm going to go with why can't I Distribute modified versions of ubuntu without permission from canonical first yak I'm not sure that would fit up there At all. I don't know that that was taken as consideration when writing the titles. I'm sorry Oddly number two. All right You're going to do a great job here guys Just pick a word that starts with why Yukon we have yukon All right, so no one won that round Can we reveal him? I kind of want to see what it should be. Let's reveal answer number two yeasty You guys are terrible people And 56 people really said that 56 people said you see An lts. Is that is that an lts release? Oh, that's fantastic Can we see answer number three, please Yodeling yodeling yet answer number four, please Yawning yawning yet answer number five Youthful answered number six Yelling and answer number seven, please Is by chance the person that said yo play here No, I didn't think so All right, so the the funniest answers that I found for ones that someone in the community Wanted the next version of ubuntu to be called We're not necessarily funny for the names. They were funny for the justifications in this case The first one was yahoo yahoo yak And the comments i'm going to read it for you Because of all the troubles yahoo is having this can only help them And who really wants to see marissa mire fail None of us do And that was by jim saint Luger is jim here jim you won a prize Come on up jim Keep in mind that one of them is the minecraft Which isn't actually here you can't you can't be one of those two or an invisible minecraft Okay, you're picking the minecraft. I'm ryan sireps. Please stand up Right see this guy he has he theoretically has your minecraft So have a conversation work it out Ship a minecraft to him after you've shipped me mine if you would You might need a microphone there master I'm gonna give jono a chance to like limber up a bit You get the jono you're ready now when i find you and stuff ready All right Round three I haven't even asked the question yet. You guys are a little Talk about premature button pushing jeez all right George jono What do you think the spirit animal for the open source? I was actually gonna say blah blah blah blah blah I'm gonna finish the question. Sorry you did it. George had to do for go ahead Oh answer. Yeah penguin penguin Do we have penguin? I told you they were deeply disturbing All right. Are you guys going to play or are you passing on that you're passing on that one? All right Who's up? Mr. Mr. Bacon. All right jono in the spirit of this evening. I think chicken Can we see chicken?  That was a tight pun That was awful. That was awful. Truly awful You you are not invited back next year just for that. Mr. Lungduk Contractually I must Go with chameleon Do we have chameleon? We might go three and out here. I know we're not looking good Jeremy In the spirit of the last question. I'm gonna go yak Can we see yak?  It's it's not looking good boys. It's not looking good And this is what happens when you have a team made up of freedom haters The gloves are awful. Hey Oh, yeah, that's right. You want all right. Yeah, you want sorry All right, let's let's quickly reveal the answers Number two Number two there you go I like your style awesome How did john owe beat me?  Langridge I don't Versus mr. Garrett All right Name something you might see happening during the hallway track at scale matthew Conversation Can we see conversations? Are we gonna play or are we gonna pass? I think we'll pass we're gonna pass really All right, let's do it me You in the spirit of the last round. I think I might say Brian Lundig All right, let's see if Brian Lundig will be happening during the hallway track. He will not. Joe. No people drinking coffee Can we see people drinking coffee? Brian, I'm not voting for st. John. Oh, that's what I was gonna say All right, you know what? John o bacon Can we see John o bacon? We are not very good at this I'm glad about that These guys are taking it a lot more serious than you guys are it all comes down to whether you guys answer this correct or incorrect Yeah, this is for the whole game guys Cocaine it is california I'm saying california has cocaine All right, then answer soon guys 10 it's on you nine eight seven six five four three two people asking where the beer is Can we see people asking where the beer is? Okay So let's take a look at answer number two. I'm sorry answer number one Someone desperately trying to use the wireless answer number two Joe no saying community answer number three Bad vulture presenter jousting matches with baguettes while riding hoverboard. Why hasn't this happened? I'm a little disappointed in us 73 people said that there are two days left jeremy two days left. All right answer number four people asking what the wi-fi password is answer number six Cadbury egg stories Don't go there Pretty gets died a little inside Answer number seven a complete lack of unused electrical outlets I think gareth may have been fiddling with the results No, we're completely on board here. We have three prizes to give away. All right. Uh, so the the funny uh, also two The funny The first one was a a fist fight between brian and rms And that was said by ryan Ryan come on up Here's the mycroft I would go with the mycroft ryan. It looks like a quality item Say good genesis There you go. Say good genesis and the other funny one The other funny one was someone predicted seeing a hoverboard on fire And that was ken echelby. Is ken here? Ken you have won a prize all right thank you to And the bad voltage family Thank you gareth So that was top notch gareth in honor of your wonderful work. We got you a little gift Oh boy, mainly it's thematic People have a problem seeing you at eye level So we got you a little hello kitty stool to stand on this is awesome.  I'm not sure what I think about that I have no idea what that's even a reference to Family feud yeah, I don't watch it. I am fairly fairly certain that that violates our code of conduct And if it doesn't thankfully it will by the time I get backstage All right Thank you to the panel as well. That was family feud Thank you guys. Thank you All right, our roadie friends. Could you come and remove all this stuff for the stay for us? Yes, roadies So we're basically at the end. Thank you for sticking around. I'm sorry about all of the av problems We had earlier on we have really no idea because the av team at the back is just being incredible from day one So give him a big round of applause by the way And and thanks to Tara for running family feud she did a quick ass job back there Tara was running the slides for Family Feud and she had to deal with the most incomprehensible massive nonsense that he wrote. It's true. It was that web app So it's not incomprehensible. It's software artwork is what it is Anyway, but we just don't thank you very very much to Tara. Thank you for having her Give it up for Tara So thank you av people and hello We want to give one of these away We really do So, uh, aren't you glad you stayed till the end now? All right. So one of you Jeremy, do you want to explain this? So The show has been kind of woolly wonka-esque. So in that vein in this room Under one of your chairs Is a golden ticket the person who gets this golden ticket courtesy of za reason Gets a free laptop Now it is On the very front piece taped So it should be very easy to find and I put it there. So someone's sitting in the chair Here it is You got it No, no In this section, I will say so if you're in the section look again or it fell It fell off after upscale Turning into load of the flies all of a so right on that plastic hard piece right in the front Yeah There it is Thank you to za reason for this strut laptop. Thank you very much za reason congratulations All right, so um, congratulations for the golden ticket Thank you to za reason. Let's wrap up with a few quick things So thank you again to all of our sponsors. Please give them a massive round of applause. Thank you very much Thank you. Thank you to Microsoft. Thank you to Pogo Linux for the great workstation Thank you to za reason for the laptop Thank you to ticket master and thank you to scale really really seriously Thank you to scale now. We've already thanked One of the members of the scale committee right gareth guys heart with the ears Did a really good job, but there is someone else There is Done a terribly good job We would like to say a big thank you to elan rubinovic and we have a present for him Tell him what it is jason It is a bottle of bourbon You're welcome And we have a kind of a secondary gift that dovetails with that because as you can see we've made elan do terrible things two years in a row Much Much to the chagrin of meru So we got her a nice plush penguin to make up for our idiocy So thank you maro wherever she is if she's here probably not This is for you. Oh, she's right at the back. She's at the back crying. Yeah, she is So they say thank you tomorrow for letting us boil So one more thing for us to talk about which he has no idea about This is true. This is new Having seen this slide deck 400,000 times in the last week This fine gentleman is going to be 40 years old and Barely looks a day over 50 so And we're going to be celebrating after this and you're all invited Although the one more thing is very steep jobs asked so apropos for you to be like this. Yeah, I do so we decided to reach out to some of stewart's nearest and dearest and have them send us a message um, so Audio fellas at the back if you don't mind making sure that we can hear this But here are some wonderful people sharing their birthday spirit towards stewart Hi stewart. This is rocker queen. I just wanted to wish you a happy birthday We've always suspected you're going to be able to get so it's good that we've got official confirmation. I hope you have a great day Happy birthday stewart. This is Matthew Ulster also known as stop waffle.  Happy birthday Getting older sure beats the alternative Happy birthday. This is Reverend Ted your big ginger overgrown british school boy Hi everyone former internet celebrity Adam sweet here I'd like to wish happy birthday to the big ginger web lethario himself stewart's aquarium language Happy birthday Hi stewart. Ron Wales lady here. Happy birthday from Wolverhampton. Ron wow Hi everyone. It's well here from Ubuntu. Sorry. I couldn't be with you today to collect this award. What? What do I get it? Oh, well, happy birthday stewart. We're all up for me and I look forward to having a few beers with you soon This is my parents by the way. Jono's mum and dad. We're not really performers, but what we wanted to do was to say Happy A very happy birthday to stewart Who we are delighted with his friendship with Oh So we're going to sing a song now I want to sing a song. Happy birthday I really Right Happy birthday Happy birthday, dear stewart. Happy birthday to you Which because you're so old you forgot to attend. I just like to say Well, uh, just I have no idea who you are That's two years fewer than the kilometers that I ran this morning. I don't think from your strange dialect, but We had over has had a saying to keep going. Happy birthday. It's my wife, by the way Once a year sometimes when we get together it feels like yesterday and I know Jono and I are both really lucky to have that in you I'm so glad you guys have stayed such good friends Thanks so much for all the awesome memories and here's to another 40 years of fantastic times, happy birthday Hey stewart, it's Michael Hall. Finally got you there to have a script script you wanted. Happy birthday. Happy birthday stewart language This is chris hyman You've made it to the decade of wisdom Hello stewart. I'm recording this on my bungee friend, so I hope he comes out That is excellent. I have to say He's pretty cool, isn't he? Yeah, he's all right So we're gonna go have some fun Was not expecting that Good, so Would you allow, well, I would say would you allow me, would you allow ticket master to buy all of your birthday drink on my behalf? Okay, so Bodega wine bar, those of you who don't know Bodega wine bar, it's literally just across the road in the little shopping precinct, but so Thanks again to ticket master and we will see you out. Thank you very much ticket master We're all off for a birthday drink for me. Thank you very much for coming And thank you for putting up with the before everyone runs out. Um, I have a small Token of my appreciation for the badge voltage folks Jeremy I don't even want to open that jono Don't open it yet Brian, well, I thank you stewart Don't know what them yet Anyone's future reference if you really really want to freak jono out Tell him you're getting something custom made with his name on it It will drive him insane the last two weeks Every other day. Hey, what are you getting made? Why do you need my name? Why do you need my size? So go ahead and open them. I would have thought it was a jano emblazoned cadbury egg I am honored sir. Thank you very much Brian Sweet Wow, you guys are great See you guys if you want a free shirt, all you got to do is this I'm be named brian All I'm thinking of throwing yours out into the audience. Oh I'm keeping this Exactly all you have to do is use non-free software and break it back. All right. All right. See let's go guys All bodega We've been bad voltage. Thank you very much


Hey, so today I'm going to talk about founding secure computation on blockchains. And this is joined to work with Whipple and Abhishek. So what is the main motivation for it, blockchain? The existence of blockchain, whether irrespective of your individual views on its existence, it exists. And more concretely for us, we want to examine the foundation of secure computation in the context of blockchains. So what does that mean? Now, parties no longer just communicate with each other when they run a protocol, but they also exchange messages with the blockchain. So what does this mean? So we want to ask the question, which is, what change does this make to the study of protocols in the setting, if any? And the first step in this process is obviously going to be establishing a model. And there's been this really, really nice line of work recently, which capture the essence of blockchains and actually prove that under certain assumptions, these blockchains actually satisfy this property. And this is a work starting with this work in 2016, and it's still sort of ongoing. But for this talk, I'm going to consider a very, very simplified model. And it will suffice. The main ideas and challenges in this work can be illustrated in this really simple model. And you'll see that this model is sort of unrealistic in some sense. But I should point out that in our paper, we actually consider the full realistic model. OK, so what is the model? So the model assumes this oracle, which I'll call the blockchain oracle. And it also has an additional timer with some parameter delta. So the delta here is to sort of indicate the average time blocks are created in a blockchain. So over time, parties send messages to the oracle. And after completion of this delta, this oracle collects all the messages along with some identifying information, sends it back. And now we require some certain properties from this blockchain. So what are some of these properties? One is we want all parties to have a consistent view of the blockchain. Next, we want that if messages are sent, they should appear immediately on the next block. And then the third property is that only the oracles can create blocks. Again, this is a super idealistic version of the blockchain. In the paper, we consider a more realistic model. Cool. So we're talking about something what we call a blockchain hybrid model. And what does it mean? I'll say a party is blockchain active if it can sort of read and write to the blockchain. Now, when establishing the model, an important thing I need to note is that the simulator has the same access to the blockchain as every other party. This is in contrast to some other recent work where the simulator can potentially even rewind the blockchain and so on. So this gives the blockchain, in the case where the simulator can rewind, sort of a local flavor of the blockchain to the protocol. While in our setting, the blockchain is sort of global, wherein other protocols and other things can also use the blockchain, independent of this. All right. Great. So I'm going to state our results, first in terms of for zero knowledge, and then more general secure computation. So for zero knowledge, we show that if only the adversary is blockchain active, then black box zero knowledge is impossible. Then we show in the positive result that if we mandate all parties to somehow use the blockchain and we see how, that we can actually have a zero knowledge protocol in this setting. So this is a super constant round protocol. And in fact, this is tight, and we show that a constant round black box zero knowledge in this model is impossible. So for this talk, I'm going to focus only on the first two. And you can see the paper for the impossibility result. So moving on to more general secure computation, we sort of overcome the impossibility and show that concurrent secure computation is possible in the setting. But not everything is all rosy. We also show that universally composable commitments are impossible in this model. Sure. So again, I'm going to focus only on the positive result in this setting. So the main thing I want you to take away from this talk is that in context of secure computation, the blockchains have both destructive and constructive use cases. So let's jump right in. And I'm going to start with zero knowledge and a very, very quick overview of the definition of zero knowledge. So here I have a prover and a verifier, and the prover wants to prove membership of some statement x. And it does so by exchanging messages of the verifier. And there are some properties that typical protocols require. One is completeness, meaning that if the statement is actually in this is a member, then the prover can convince the verifier of this. The second is if the statement is not a member, then no matter how the prover behaves, it shouldn't be able to convince the verifier other than with some really small probability. And the third is when the verifier is trying to cheat, where it's trying to sort of glean some information from the prover that it doesn't already have. And this is defined with respect to an ideal world where only the verifier exists, but not the prover. And this is formalized by saying, there exists some entity called the simulator, which has the same input as the verifier. It doesn't get the additional input that the prover does. And it's able to somehow generate a transcript that looks the same to the verifier. So the verifier is now able to learn any information by itself that it could have learned from the prover. That's establishing this property of zero knowledge. But now in our setting, we have this blockchain looming over us and this definition just to indicate that. So what about the impossibility? So in terms of black box protocols, the advantage a simulator in the black box setting has over a regular prover is that the simulator is able to rewind the verifier or an adversary. It's able to make the adversary go back in time. And so the main idea here is to construct a verifier that prevents a simulator from rewinding. So the idea is really simple. So every time the verifier has to send a message, it takes the transcript so far, puts it onto the blockchain, and then waits for a response. Once the response arrives with the message, it checks if there's a different transcript for the same session already on the blockchain. So for a simulator to be able to rewind, there must be at least two partial transcripts of the same session on the blockchain. So the verifier will never respond to the prover if it finds another session. So this prevents the simulator from ever being able to rewind the blockchain in the setting. Note that here only the verifier is using the blockchain. The prover is sort of oblivious to the existence of the blockchain. So this is going to be an important point where we show that it's impossible if only the adversary's blockchain active. And but if all the parties are blockchain active, then we actually show some positive results. So the structure of the zero-knowledge protocol follows this preamble approach from Prabhakaran, Rose, and Sahai. And specifically, it has these three stages. The first is the verifier committing towards a challenge. And the second is what we're going to call extraction opportunities or slots. This is to enable a simulator to extract the challenge that the verifier commits to. And the last phase is going to be the proof system. Concretely, you can think of it as the Hamiltonicity proof system or something like that. So why do we enforce this structure? This structure is useful because it gives you the simulation guarantee that if you're able to extract the challenge in even one of these slots, then the rest of the protocol can be simulated in a straight-line manner, no more rewinding. So if I'm able to rewind once during these slots, then I don't have to bother with rewinding any time in the future. So let's look at how this protocol could potentially work. So now we have the blockchain. And the main idea is to use the blockchain as a course timer. So what does that mean? That means every party is going to have a timer with some timeout parameter k. And every time a block comes, it's going to come down on the timer. And then it's going to run the protocol. So for instance, I should note importantly that parties are not required to post anything on the ledger. So the use of the ledger in this protocol is only going to be read. So for instance, say they run this first slot and a block appears, both of them added. And the second block appears, so on. And say now the third block appears. Here I'm assuming the verifier is cheating, so it hasn't updated its local state. But the prover sees, OK, my timeout was three and there are three blocks here. I'm done. And the verifier hasn't completed, so I'm going to abort. So the question is, why is this useful? How does this help us? So we want to recall the impossibility. We want to stop the adversary from preventing rewinding, right? So contrary, let's think of the case where you have four slots and a timeout of three. And then if the protocol actually computes, you're going to have potentially less than three blocks. So the yellow arrows indicate a block appearing during the execution of the protocol. And now I'm going to call the blocks where the slots where a block appeared as bad, and the slots where the block didn't is good. Now I have two good slots where the adversary is not waiting on a block, right? Now I can potentially rewind the adversary to my heart's content, extraction, done. So are we done, though? And it turns out there is a really small, subtle issue which shows up in the context of this setting is that of timing leakage. What does that mean? So it means that simulation typically takes time larger than the running time of the adversary, of the honest execution of the protocol. So in, for instance, concretely, think of this really bad case where the actual execution runs, it maybe takes one block duration in the blockchain world. But while simulating it, it takes three blocks duration. And this is now trivially distinguishable by a distinguisher who has access to the blockchain. So the important point to note is that the time the simulator takes to complete simulation and the number of computation steps that the simulator takes are slightly different, right? So now what we can hope to do is, if it's parallelizable, do some of these computation steps in parallel, and then hopefully there is no timing leakage. And this is exactly what we do. So we have this notion of a main execution, and we have the notion of a rebound execution. And note that these are run in parallel. And I've indicated by the height to be the duration that the verifier takes to respond to the challenges or the execution of the slot. And note that even for the same slot in the rebound execution, the verifier can potentially take longer. And what's the main difference between the main execution and the rebound execution is that the main execution, you isolate the adversary from the blockchain. Meaning any query that it sends to the blockchain, you don't send it. Anything that the blockchain sends, you don't send to the adversary. So what does this mean? So if I have potentially blocks coming from the blockchain, I know that in these blocks on the rebound execution, the adversary is expecting a blockchain, a block rather. So these are all bad slots. Now I'm guaranteed there's at least one good slot, and I can rewind. And this is pretty much all we needed, right? Once we get one slot where we can rewind, we're done. So it turns out that for simulation to, for extraction to succeed, we need at least super constant many slots, which in turn means we need super constant many rounds. And unfortunately, this turns out to be tight, and we show in the paper that there does not exist a constant round protocol in this setting with black box simulation. I should note that there are some similarities, superficial similarities to the timing model where parties have synchronized clock and have delays to make protocols work, but there are slight differences in the setting. In the timing model, the simulator can control the clock. Here sort of there's an unforgeable clock from the blockchain. And in their timing model setting, the adversary can be rebound at any point, and but here we have this notion of safe and unsafe, and this requires actually new rewinding techniques. Okay, moving on to concurrent self-composition. So what is secure computation? A really, really quick overview. Parties jointly want to compute a function of the private inputs, they communicate, and at the end, everybody gets their output. So how do you define security? Security is defined with respect to an ideal world where everybody sends their inputs to an ideal party, and the ideal party computes the output and sends it to them. So you say that for every set of corrupt parties executing the protocol, there exists a simulator that corrupts the same set of parties and the views are sort of indistinguishable. You don't need to really know what the exact definition is to proceed, but again, to know we have a looming blockchain. So let's consider three protocol executions. These are the transcripts of the execution of the same protocol with potentially different inputs. So I consider this notion of only self-composition where it's only the same protocol that's being run, as opposed to general composition where I might have protocol A and protocol B messages. And the self-composition allows for arbitrary interleaving. So I can concurrently arbitrary interleave the messages. And why is this model interesting? It turns out that it's impossible in the plain model. So what do we do? The prior work typically takes, you know, there are some weaker security notions, or alternatively, you establish some trust assumptions. In our setting, we construct a protocol in the blockchain model. So what does that mean? It means that our protocol works in a sort of decentralized trust assumption, right? So it's not like we're somehow overcoming the impossibility. We're showing that it is possible to construct a protocol, and this implies that, you know, it's sort of in the decentralized trust assumption. Okay, so just quickly to summarize why the impossibility holds. It was initially showed by Linda in 2004 that it's impossible in the black box setting, and this impossibility was extended to the non-black box setting and, you know, various other models. So the basic idea is this. If I think of blue as one protocol execution and green as the other, say I need to rewind at this point. And the adversary at green has committed to its input. But the problem is now when I rewind beyond the input commitment phase, the adversary can potentially change the message or change its input. And this leads to a whole lot of problems during simulation and it's something that we want to avoid. And I'll come back to this point in a bit. Okay, so the structure for our concurrently secure computation to identify what we need is based off these, you know, works in weaker models and the protocol works like this. Most of this is sort of immaterial, but I'll focus on the important part. So I have some notion of a trapdoor generation. I have a commitment phase. I have coin tossing and then the actual protocol. And it turns out that it's sufficient to build a commitment scheme that's concurrently extractable. And once I do that, the rest of the protocol as before can be sort of simulated in a straight line manner and I don't need to rewind anywhere else. So the point is that I now need to build this concurrently extractable commitment scheme. And the structure is the same as something that you've seen before when I talked about the zero-knowledge protocol. I have a commitment, initial commitment phase where the committer commits to a message. And as before, I have these extraction opportunities or slots. So remember, the impossibility stemmed from the fact that you were rewinding beyond the sort of, the input commitment of a party.  So if I commit to the blockchain, there's one would hope that there's no way of going beyond it because now I've committed something to a blockchain, I can't change the value that I committed to the blockchain. So the idea is this. Now, the first message, which is the commitment, sends it to the blockchain, waits for a block to be created. Now, both the committer and the receiver have this commitment, right? Now, as before, they have this timer and they start the execution of the protocol. The rest of it is identical as in the zero-knowledge case. But how do we extract? Remember, now, because we are in the setting of concurrent execution, the slots itself might be split over multiple rounds, right? And now they might be interleaved with other slots and rewinding one slot could potentially lead to rewinding other slots and so on, and this leads to an issue, right? And to solve this, we look to this really, really nice work in this sort of independent setting or a different setting by Goya, Lin, Pandey, Paas, and Sahai, and they talk about extraction in the presence of a constant number of external messages. They show that if you have a constant number of external messages, then you can construct a concurrent, secure, concurrently extractable commitment scheme, right? That's great, like, can we now apply this to our setting? We have, you know, the external messages are now messages from the blockchain, and now we're trying to extract while we have the blockchain, and remember, we can't go beyond, we can't rewind beyond any of the blockchain messages because, you know, the blockchain is fixed. But unfortunately, it turns out that the number of messages that the protocol execution gets from the blockchain are not constant. In fact, you know, we can only weakly bound it by the number of protocol executions that are running in the concurrent setting. So our main challenge, which, unfortunately, I won't have time to go over, is to show how this sort of robust extraction lemma extends to the setting where we have this blockchain, where there are potentially non-constant many number of messages. And to sort of conclude, I've shown you sort of protocols that the destructive nature in the sense that, you know, general protocols that we know don't extend to the blockchain setting, and then we have these constructive protocols where I've shown you, OK, zero noise protocol that actually works, and in fact, we are able to sort of overcome some impossibility result in the concurrent composition setting, and we actually can give a protocol in the blockchain model. And that's it, and if you have any questions, I'd be happy to take them. Questions? So these external messages that come from the blockchain in your construction, do they need to have some structure? Like is it like some actual part of the, or is it just any message from the blockchain? So for us, we assume that the blockchain oracle sends messages only periodically, and it's identifiable as, you know, blockchain messages. So I can't force them, in the simplified model, at least, yes. So actually, this is also for the zero-knowledge protocol. You sort of just use the blockchain as a timer. Yes, for the zero-knowledge protocol, we use it only as a timer. But for here, you actually have to post a message to the blockchain. So can you, like, wouldn't it also make sense to use the blockchain also, like, for some kind of computation in the protocol? Sure. I mean, so we want to use it in a minimal sense, right? We are just saying, OK, the blockchain exists. We are talking about the most general setting, you know? This is, in an idealized world, this is what one would hope a blockchain gives you. We don't know about, you know, can you do computation on the blockchain? Maybe it's sort of orthogonal. Why shouldn't the simulator be allowed to rewind the blockchain? OK, so that's more of a different philosophy, in the sense that you can allow the simulator to rewind the blockchain, but then the blockchain can be only used by the protocol that the simulator is simulating, right? Because if you're revinding the blockchain, it can't be used by another, you know, something, some other party, because now it's seeing the blockchain roll back. So you want the blockchain to be global, in the sense that I'm using the blockchain to do this, but other parties elsewhere in the world are also using the blockchain to do something. So I don't want the simulator to be able to rewind the blockchain. Do you have any restriction on the blockchain, or you can use even a Bitcoin blockchain to run your protocol? So this follows from these modelings of the blockchain that as long as the protocol satisfies these certain properties that these recent works show as modeling of the blockchain, it's sufficient for us. It's like, for instance, don't you have a space issue? Because if many players want to write, then there is a block site that is limited. Sure, those are potential issues that we sort of ignore and assume that, you know, how many of our messages are set? Every block is unlimited. Yeah, so we assume the idea. Thank you. Let's take the speaker again.


He uritendei nongātiapa, nongāti tūwharetoa, nongāti ruanui, hoki ko Jayce te patu toku i owa. My purpose and what's leading me on this journey right now stems from my own personal lived experience of mental health challenges. I've had five friends pass of suicide. I've had family members who have suffered from mental health challenges. So the mahi that has grown from my niece telling me that when your dad died, my brother died that she didn't want to be here and that she wanted to be with her father. From that came me creating this programme, M3 Mindfulness. Three M's of M3 Mindfulness. The art of learning to be present, paying attention to the now movement. I used to be a dancer in my past life, so bringing that into it's also a gorgeous way to somatically move stuck energy in your body. And then probably my most favourite part of M3 is Māori Pūrākau. Our Māori stories, our narratives are so rich with beautiful themes like love, like manākitanga, kaitiakitanga, respects. Those three things, M3, we take that into schools and share that with our orangatahi so that they get a deeper sense of themselves, that they learn how to deal and cope with big emotions like my niece. So that when sadness is here or grief is here or anger is here, they have the ability to be present in the moment and make a really calm, informed decision about what to do next.


Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored at this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which he turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which he turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth of thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that a fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by James O'Connor, February 2010. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou would still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Katie Riley. February 2010. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by to-morrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. And of poem this recording is in the public domain. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Leanne Howlett. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by tomorrow and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. End of poem This recording is in the public domain. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by L. Lambert Lawson. Escondido, California, www.dedicatedtokaren.com. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by tomorrow, and fleet in my arms, like fairy gifts fading away, thou wouldst still be adored, as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Leonard Wilson of Springfield, Ohio, February 2010. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by tomorrow, and fleet in my arms like fairy gifts fading away, thou wouldst still be adored, as this moment thou art. Let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervor and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. And upon this recording is in the public domain. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Matthew Tiscarino in Ithaca, New York, February 2010. Believe me, if all those endearing young charms which I gaze on so fondly today, were to change by tomorrow, and fleet in my arms like fairy gifts fading away, thou wouldst still be adored, as this moment thou art, that thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervour and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Nicholas James Bridgewater. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by tomorrow, and fleet in my arms like fairy gifts fading away, thou wouldst still be adored, as this moment thou art, let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervour and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes, as the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Ruth Golding. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by tomorrow, and fleet in my arms like fairy gifts fading away, thou would still be adored, as this moment thou art, let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervour and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes. As the sunflower turns on her god when he sets, the same look which she turned when he rose. Believe me, if all those endearing young charms, by Thomas Moore, read for LibriVox.org by Raven Notation. Believe me, if all those endearing young charms, which I gaze on so fondly today, were to change by tomorrow, and fleet in my arms like fairy gifts fading away, thou would still be adored, as this moment thou art, let thy loveliness fade as it will, and around the dear ruin each wish of my heart would entwine itself verdantly still. It is not while beauty and youth are thine own, and thy cheeks unprofamed by a tear that the fervour and faith of a soul can be known, to which time will but make thee more dear. No, the heart that has truly loved never forgets, but has truly loves on to the clothes. As the sunflower turns on her god when he sets, the same look which she turned when he rose.