ACM ByteCast - Whitfield Diffie and Martin Hellman- Episode 37

Episode Date: May 16, 2023

In this episode of ACM ByteCast, Rashmi Mohan hosts 2015 ACM A.M. Turing Award laureates Whitfield Diffie and Martin Hellman. As joint creators of the Diffie-Hellman key exchange, they introduced the world to the transformative idea of public key cryptography, the underpinning of every secure transaction on the internet today. Whitfield has spent a large portion of his career as a security practitioner, including roles at Northern Telecom and Sun Microsystems. He is an elected Foreign Member of the Royal Society and a recipient of numerous other awards and accolades in computing. He's currently a consulting scholar at the Center for International Security and Cooperation at Stanford University. Martin is a Professor Emeritus of Electrical Engineering at Stanford University. He's also a recipient of the RSA Lifetime Achievement Award, among many other recognitions. Both have received the Marconi Prize and have been inducted into the National Cybersecurity Hall of Fame and the National Inventors Hall of Fame. Whitfield and Martin share their individual journeys to computer science and cryptography, which were shaped both by personal interests and the geopolitical realities of the time. They also describe how they met and developed a rapport with each other as researchers. They share their “aha moment” in public key cryptography and how the internet  catapulted commercial cryptography in the 1990s. They also share their thoughts on computing privacy, national security, and quantum computing and its implications for both Diffie-Hellman and RSA (Rivest-Shamir-Adleman) cryptosystems. They touch on end-to-end encryption and the field of technology in the next five years. Along the way, they share colorful details from their early years and share advice for young people aspiring to get into computing

This is ACM ByteCast, a podcast series from the Association for Computing Machinery, the world's largest education and scientific computing society. We talk to researchers, practitioners, and innovators who are at the intersection of computing research and practice. They share their experiences, the lessons they've learned, and their visions for the future of computing. I am your host, Rashmi Mohan. If you think about the underpinning of every secure transaction on the internet today, the answer most likely to come to mind is cryptography. From keyless entry into our cars to every credit card swipe, we rely on and rest easy with secure communication thanks to the pioneering work by our next guests, the 2015 ACM Turing Award winners, Whitfield Diffie and Martin Hellman.

As the joint creators of the Diffie-Hellman Key Exchange, they introduced the world to the transformative new idea of public key cryptography. Witt has spent a large portion of his career as a security practitioner and has been conferred the Fellowship of the Royal Society, is a Marconi Fellow and a recipient of numerous other awards in computing. He is currently a consulting scholar at the Center for International Security and Cooperation at Stanford University. Martin is a professor emeritus of electrical engineering at Stanford University. He is also a published author and a recipient of the RSA Lifetime Achievement Award, inducted into the National Cybersecurity Hall of Fame, amongst many other accolades. Witt and Martin, welcome to ACM ByteCast. I'd like to lead with a simple question that I ask

all my guests. If you could please introduce yourself and talk about what you currently do and give us some insight into what drew you into the field of computer science. Witt, would you like to go first? Sure. What do I currently do? My interest is in history of cryptography, and my work, such as it is, is as an advisor to various companies. What brought me into computer science?

I wasn't really good enough as a mathematician, and I was trying to dodge the draft, so I took a job programming. That was very, very succinct. I'm definitely going to dive into that a little bit more, but Marty, I'd love to hear from you as well. Sure. What I do now is best summarized by the subtitle of a book my wife and I wrote six years ago, creating true love at home and peace on the planet. I'm also involved with Stanford Center for International Security and Cooperation, where WIT is associated. The war in Ukraine is obviously occupying my thoughts right now, working on the risk

of minimizing, trying to reduce the risk of a nuclear war, and thanking my wife every day for moving me in this direction. How did I get into computer science? I started in information theory, which was my PhD, and then there are several missing links that I'll leave out for now, but when I was teaching at MIT in the EE department, 1969 to 1971, Peter Elias, one of the original contributors to information theory, gave me a copy of Claude Shannon's paper, Connecting Information Theory and Cryptography. And that's when I realized maybe I could do work in cryptography. And so that's how I ended up here. Great. Thank you for sharing that.

You see, so he's skipped over your first question into your second question. And the reason is he only got into computer science because they came to call what we did computer science. Well, the other thing I left out is that when I was at Bronx High School of Science, they had a 1620 computer before most colleges had it. This was 1959 to 62. And I assiduously stayed away from that computer because I thought you had to be some weird math genius, which I didn't think of myself as being in those days, to program a computer. When I was forced to take a two-unit Fortran programming course in about 1964, I was shocked to find out how simple it was. Thank you. I mean, it's amazing how both of you kind of talk about yourself as not

being great mathematicians and yet have had such amazing and successful careers in computer science. I'd like to go back to what you said previously about not being good at math. Also, because I was listening to a bunch of your previous interviews and you talking about not being great at academics. A lot of young students typically feel like a lot of doors close for them because they're not getting the grades that they should to choose a career of their choice. What would your advice be to them? How did you navigate that? My advice is to have good luck. I've had incredibly good luck. I don't know how to teach that. But they're really two entirely different things. I'm not a very good student.

That's very different from not being any good as a mathematician. And yes, of course, I know more mathematics than 99% of the human race. What impresses me is that the best mathematicians I know, and for example, my college roommate could solve in a minute problems that took me a day, will be counted as nothing in the pantheon of 20th century mathematics. So I say it's a long way up and long way down. Another way of putting it is that I never learned very much about what the activity of mathematics was. So I had read Eric Temple Bell's Men of Mathematics, and thereby had learned to be a mathematics professor of the 19th century. And I didn't succeed at doing that. So I had to go into computer science instead. The thing that I would add that people should remember is Albert Einstein had trouble in school.

So school isn't designed for everybody. There are mixed claims about that. Pius claims he was quite a good student. So I'm not clear what's true about that. How did both of you meet? I mean, you've obviously collaborated and you probably brought very unique traits to the table. You've done some amazing work together. What brought you both together and what did you feel worked as a team? How did you sort of collaborate? Why don't you tell that story, Whit, because Alan Conheim figures prominently and you were there. We were introduced by Alan Conheim in 1970. My very brief biography in this matter is I got seriously interested in cryptography. I mean, I got interested in cryptography for the last time in my life.

It was about the second or third time I got interested, but it was time it stuck, in the fall of 1972. So it's been 50 years ago. And left, in the spring of 73, I left the artificial intelligence laboratory at Stanford and began driving around the country. And the first discovery I made was my wife, without whom I believe I wouldn't have discovered anything else. And she and I began traveling around together. And the summer of 1974, we visited the IBM laboratory at Yorktown Heights, which was the only significant non-governmental cryptographic group in the country at the time. And the head of the mathematics department, which was what was doing cryptography there, was Alan Conheim. And he said,

I can't tell you anything. We're under a secrecy order here. But when you get to Stanford, you should look up my old friend, Marty Hellman. He subsequently wished he'd never said that because we became a great nuisance to him. But when I got back to Stanford, I called Marty from Oakland, where I was staying, living with Leslie Lamport, as in this is a small world. And Marty, as I recall it, graciously granted me half an hour of his time on what I think of as a Wednesday afternoon, though I'm not certain of that. And Mary and I drove down to Stanford and she took the car and went off and she knew better than a half an hour. So at six, she called and Marty invited us over to dinner and as families, we got along very well,

and Marty and I worked together for the next four years. I became a graduate student because it was the cheapest way of supporting me, and in four years, I took four courses and wrote four papers, and I've forgotten what the courses were, but I've been making a living off the papers for the last 50 years or so. I've described Witt as being ABC. Most people don't get a PhD because they're ABD, all but dissertation. Witt was all but courses because he did great research. But as he said, he had difficulty with courses. When homework assignments were assigned, he would get under his dots and work for hours to avoid doing what anybody had told him to do. He's very independent. That's great. That's great to hear. And it's amazing to hear that what he talks about in

terms of saying, hey, the research work that I did has really sort of taken the direction of my life. So, Marty, what is, in your thought, I've heard so often from entrepreneurs and from others that finding the right partner in order to be able to solve a great problem is the most key thing and the most difficult thing. In your case, you both sort of found each other. Is this a problem in terms of the world of cryptocurrency? Is that something that you had already envisioned as something you wanted to solve? Or as you both got together, the problem sort of started to define itself?

More of the latter. I wasn't looking for anybody. All my colleagues told me I was crazy to work in cryptography. In fact, I have a talk on the wisdom of foolishness. It turns out most of the great breakthroughs are seen as foolish a priori. I gave a talk, I was honored to address the annual meeting of Nobel laureates three and a half years ago. And I asked five of them before my talk, whether the work that won them their Nobel prizes had been encouraged or discouraged as crazy for the five crazy. So when Witt showed up, it was, you know, just like, well, you know, Alan Conham said he should see me. So I set up this half hour meeting, but it was clear immediately, almost immediately that there was a real meeting of the minds. Witt was interested in the same things I was, some different things. I was interested in some

different things, which is why we ended up going to 11 o'clock that night. There's no question that finding Witt was a key part of my life and my contribution, although I didn't know it at the time. My description of it is that each of us found the other one, the best informed person willing to talk about cryptography that he had encountered. for the rights of research to be done in a more sort of democratic way in this area, for papers to be published in this space and not necessarily have governance over it. Would you care to talk a little bit more about that, why that was important to you and what you were sort of hoping to do with it? Yeah, well, I kind of fell into it, as did Whit, I think. Originally, I didn't think there would be a problem. But then as problems surfaced, and the government started to make noises, even threatening to throw us in jail if we continued publishing our papers,

I grew up in the Bronx and I wasn't a very good street fighter, which this wasn't a bad neighborhood, but still I got beat up a lot. And so I became a street fighter with my mouth and my mind. And I think that was what the government didn't realize. And I think it has a similar personality. So we just wouldn't back down. I mean, we had a choice of either backing down or continuing. And it was just obvious that you don't back down, especially this was right after Watergate.owl, an unsentimental memoir of the Lower East Side. I don't remember who wrote it, but you can find it. It's about somebody who had the same response that you did, applied his brain to becoming tough and grew up from being a gang member to being a crooked lawyer and a corrupt judge.

Well, in my case, I never was a gang member. But as I look back on it, no wonder the other kids beat me up. Because I remember one argument I was having with another kid in the neighborhood, is to, is not, is to, is not. I'll bet you a dollar. I'll bet you a hundred dollars. I'll bet you my house against yours. And then I said, you don't even own your house. We lived in a two-family house and he lived in an apartment. No wonder he wanted to beat me up. Okay. I would love to understand, did you either of you have sort of, while you were working on this problem together, do you have like an aha moment where you're like, oh my gosh, this is exactly what we were trying to get to when you got to sort of solving the, or coming upon the concept of public key cryptography?

Yeah, I think there were two. Whit had one and I had one. Why don't you tell yours first, Whit? So I had been working on two problems, one for five years and one for 10 years. And in modern description, the 10 year one we would now call key management, you know, hadn't been devolving much time. I didn't think of myself as working in cryptography. I just had become aware that the problem of negotiating keys, I didn't know how to do it. And then five years after that, I became aware of the problem we would now call signatures. And then in 1975, I set out to try to confine the virtues of Unix login with the virtues of what's called identification friend or foe between radars and aircraft and came up with digital signature. And a few days later, I realized if you turned my approach to that around, you would solve the key to key negotiation problem. And at that moment,

I understood that I had discovered something. Yeah. So basically, Whit came up with the concept of a public key crypto system, but didn't have a workable system for either key exchange or digital signatures. And we, along with Ron Rivest, I didn't know Shamir and Adelman were also working on it with him. And Ralph Merkle, independently at Berkeley, was working on this as well. And my aha moment was in May of 1976, when by this time we were all talking with one another via snail mail. We did not have email in 1976. I came up one night at this very, I think it's this very desk where I'm sitting now, with what's now called Diffie-Hellman Key Exchange. I was playing with discrete logarithms. John Gill had suggested them to me. He had been one of Manuel Blum's students at Berkeley. And he was a colleague of mine here

at Stanford and assistant professor of electrical engineering. And I was playing with Y equal alpha to the X, trying to turn it into a public key crypto system. And lo and behold, I came out with a Merkle public key distribution system instead, which is now called Diffie-Hellman Key Exchange. That's incredible. Did you imagine the absolute widespread use of your work when you first came up with this idea? Well, Whit came up with the first sentence of our paper, New Directions in Cryptography. We stand today on the brink of a revolution in cryptography. And that was 1976 that we wrote that. We thought that within five or 10 years, commercial cryptography would take off. It took more like 10 or 20. In fact, the internet in the mid-90s really is what catapulted it. Today, public-key cryptography protects over $6 trillion a day in foreign exchange transactions alone, plus our piddling banking transactions,

and digital signatures are essential to software updates, trusted authentication, things like that. Internet commerce in general. Oh, yes. E-commerce in general would not be possible without public e-cryptography. Have you both been sort of involved in the evolution of the algorithm that you first came up with and continuing to see how it's sort of evolved and especially in the use cases that we currently encounter. How have you stayed engaged? Well, Whit's been more engaged in it than I have. Remember, this was 1976, 1980. My wife and I got married in 67 and we'd screwed our relationship up pretty well.

She was ready to leave me, although I didn't know it. And she decided not to and was instead looking for catalysts. And she got involved with a group called Creative Initiative that morphed into a group called Beyond War, in which we worked starting in the 80s. I really shifted my interest in the starting around 80, 81. I was just involved in the early days of it intensively, whereas WIT has stayed more deeply involved. Great. I would love to touch upon that as well, Marty. But did you have more to add in terms of how you found yourself

sort of continuing to stay engaged in the world of cryptography? What did you feel, how it was evolving? Well, yes. So, I mean, the one very big thing that happened over these last 30 years is that it turned out, although RSA, the crypto system of S. Shamir and Edelman developed, has continued to be tremendously important. Diffie-Hellman is, so to speak, more flexible. And there was a transformation that Diffie-Hellman is less done these days over the sort of finite field we imagined and done using what's called elliptic curve cryptography. But the protocols are all the same. What I did over my career was work on, I sort of morphed into a, into a cyber security person because I had essentially, I had the same job at two different places. I was the quote,

manager of secure systems research for the Canadian telephone system. And then I was chief security officer for Sun Microsystems. And both of those are a matter of applying cryptography and other security techniques to solving real problems. Right. Yeah, no, absolutely. And I think that, I mean, I was reading about you sort of being in that chief security position and also sort of, And also, did that ever morph into building algorithms or beyond just the organization and thinking about security from the organization's perspective? How did your research evolve?

I mean, I actually did design a cryptographic device one time. Northern Telecom manufactured it. ACM ByteCast is available on Apple Podcasts, Google Podcasts, Podbean, Spotify, Stitcher, and TuneIn. If you're enjoying this episode, please subscribe and leave us a review on your favorite platform. So, Marty, maybe going back to your own thoughts around, I know that you've been doing a lot of thought around rethinking national security. I was reading a little bit about your work and your interest in that field.

I'm wondering if you could talk more about it. I know there is a personal journey associated with it, but you're also thinking about it at a much more global level. Well, the two really go together. In the book we wrote, and people can download a free PDF from my Stanford website, one of the soundbites is get curious, not furious. And so when Dorothy, my wife, used to do things that seemed crazy to me, I treated her like she was crazy in the old days, which drove her crazy, which convinced me I was right that she was crazy. It was a feedback loop. Now I go to her and I ask questions. I say, I can't get over

feeling that what you're doing is crazy, but I know you're not. What am I missing? Every time she has a different way of looking at it, just a orthogonal view. And the same is true internationally. And so we need to ask more questions. And the evidence that the societal method of managing marriages or international relations is not working, there's a 50% divorce rate that shows it at the marital level. If you look at the wars that the United States has been involved in over the last 40 years, every single one of them, I believe, has been needless and has hurt our national security rather than helped it. And yet we don't learn from our mistakes. We really need to rethink national security. And I'm very honored that a former Secretary of Defense, a former Director of NSA who wanted to throw us in jail 45 years ago,

now a good friend, Admiral Bobby Inman, and a former Chairman of the National Intelligence Council have all signed on to a statement of support for rethinking national security. Basically, in this age of nuclear weapons, pandemics, cyber attacks, terrorism, global environmental crises, we ask, is it possible that national security is becoming inseparable from global security of all nations? And if so, how do our current policies need to change? We're convinced that, in fact, the question has the affirmative answer, but we ask it as a question because that's where we had to start. Understood. How do you think this sort of applies to a layperson, right? I mean, there's, of course, when we're talking about policies, definitely one of the biggest ways that we can influence that is

to vote and vote into what we believe is the right causes. But how else do you think an individual can get involved? Actually, the best way to get involved is the way I started, which is not trying to make the world a better place. I mean, I was kind of standard on that. I said I cared, but I didn't really. It was when I was in pain in my marriage. And so the best thing a person can do is to start getting curious, not furious in his or her interpersonal relationships, carrying that over to the international, asking more questions like, what do we really know about the war in Ukraine? What do we really know about Putin?

What do we really know about Zelensky? And it turns out many of the things we think we know turn out not to be true. Some of them are, but not all of them. Being more inquiring, especially before we go killing people, we need to really think things through. We have not done that as a nation. And it's not that the United States is uniquely damaged that way. Every nation behaves that way. But as an American, I try to change my own nation because that's where I have some hope of doing it. And I think everybody has that opportunity. Everybody has the chance not

only to write to their congressman or congresswoman, but to meet with that member of Congress. On my Rethinking National Security page, on my Stanford webpage, there's a link to what you can do. And the last item is to meet with your member of Congress, and it explains how you might bring that about. And that can really make a difference. Got it. Yeah, we'll definitely share the resources, but that's very insightful information, seeking the answers, making sure that you fully understand them before you can act upon them. Great advice. Yeah. And just one thing to add, I've been very amazed that when I talk to people who are part of the national security establishment, a number of them have told me that reading my report on rethinking national security, which

examines, I think a dozen assumptions that masquerade as self-evident truths. One man told me that his brain was quicking the whole time. I mean, it's things that he hadn't really thought about and that we need to think about. That is amazing. And I'm really looking forward to sort of all of the resources that you're going to share. There's a connection back to public key cryptography. It's questioning assumptions. There was an assumption in cryptography that you couldn't have a public key. In fact, when I talked to Horst Feistel, who is one of the key IBM people in the area, I only had 10 minutes with him before we had Diffie-Hellman Key Exchange. He said, you can't do that. And that's because there was a general

rule in cryptography that all security must reside in the secrecy of the key. So how can you have a public key? Well, you also have a secret key, but that's the thing that people miss. And so many of the great ideas, both technical and otherwise, come about as a result of questioning the conventional wisdom. Absolutely. Yeah. Questioning assumptions. I think that's excellent advice.

Thank you for sharing. Whit, I'd love to pivot back to you in terms of, I know that you spend time working with startups or advising entrepreneurs. What has been your sort of experience? What have you enjoyed most about that journey? You know, it'd be a standard answer. I get to talk to lots of interesting people working on lots of interesting things. How do you feel that they're able to sort of, I mean, so you're obviously advising them

from a business perspective. Do you do a lot of technical advising as well? Because one of the things that I know we've already spoken about is a lot of startups don't always have the wherewithal to have a large research team, but pairing with maybe academic researchers might be immensely beneficial for them to really further the technology journey that they're on? I think my virtue in this field is length and breadth rather than depth. That is to say, I've been watching it personally for 50 years, and I have studied its history in a good deal of detail. So I can teach people not

just about technology, but about projects and policies and people and so forth. And so I think I bring cryptographic culture with me. I also think one of your greatest strengths is the fact that you question conventional wisdom. I mean, you did that continually. You're a rebel. Okay. Right.

You know, so I make snide remarks about my clients' work. They're inviting you in. They see a great value in it. I'd like to pivot the conversation to ask you, Whit, to comment on what you think might be the effect of quantum computing on the field of cryptography. There are some very dire scenarios that are floating around. I wonder, what's your perspective on that? at its summit in New York a month ago. It will destroy Diffie-Hellman and RSA, the public key crypto systems that have been the workhorses of the last 40 years. But there is a whole set of new mathematical approaches to these problems, particularly what are called lattice-based crypto systems that are being proposed now as standards to replace the systems we designed. Do you think that those are ready for prime time? Not to say

that quantum computing is ready for prime time, but what do you feel in terms of how ready they are, how well tested they are to be used in the field? I can't report that I've evaluated them and like them or anything like that. If you look at our experience, and we've had, this would be the third experience roughly of its kind. That is to say, it took our systems one or two decades to be generally accepted. It took elliptic curve cryptography approximately the same amount of time. So it might take these the same amount of time. I can't tell you, I don't know anything about whether any individual one is going to be successful or not. Something important is even if quantum computing becomes a threat 50 years from now, things that are protected today should still, many things should still be secret 50 years from now, like your medical records. So I think we really should be paying

much more attention to this. Plus, we need to be looking not only at quantum computing, but at possible breakthroughs in factoring and discrete logarithms. I've proposed as a theoretician, I can do this, that we should use two key exchange methods, Diffie-Hellman for one, your key distribution centers, which is a classical approach, which has a lot of problems with it, but then you exclusive all the two keys together. And if either system stays secure, you're secure. And of course, this increases the cost, but that doesn't bother me as a theoretician. In the same way, I think digital signatures should use a public key digital signature, as well as a Merkle tree signature. You sign a message twice, and if either signature stays secure sign a message twice. And if

either signature stays secure, you're secure. And so I think we ought to be doing things like that as well. And Merkle tree signatures have the virtue of not requiring secrets. If you have a secret, you have a vulnerability. Anything that uses secrets has problems. Yes. Tree signatures only rely on one-way functions. Got it. Thank you. Thank you for sharing that. So there's a lot of talk around popular messaging platforms introducing end-to-end encryption. What are your thoughts on this topic or any sort of governance in this area? Government has undergrown a growth over the last few centuries, rather analogous to the growth of the God of the

Jews, who was once the God of the Jews, and then they eventually decided it was the God of everybody. And government was just one element of society and now thinks it is the essence of society. And so it thinks that what government doesn't want or would make some of its work inconvenient, it shouldn't have. And I think that individual rights, privacy, autonomy are what government exists to assist in and are not things that should ever be compromised toward government's convenience. Marty, do you have more thoughts around the end-to-end encryption as well? Well, let's talk about what are usually thought of as back doors in phones and things like that. It's interesting that 20 years ago, 30 years ago,

both NSA and the FBI wanted weak encryption or wanted this back door. I would call it a front door since everyone knows that it's there. Whereas more recently, it's been only the FBI that's been asking for it. And former directors of NSA have actually said that they're wrong to want that. And I think there was a report by a number of cryptographers, including Ron Reves, called keys under doormats. And I think that describes it well. You can't see, I don't see any way you can build in this back door, front door to a phone without creating keys under doormats, basically. It's a very dangerous thing to do. And the other thing I would say is that when the FBI says all they want to do is go back to the good old days, when they got a warrant to wiretap, they could wiretap. Well, today, maybe half the

stuff they intercept is encrypted, but they're also getting 100 times more information than they got in the old days. They have license plate, automated license plate readers. They've got the security cameras that record. They're probably getting 100 times as much raw information, half of which is unavailable to them, which of course frustrates them. And I wish there was a way to give it to them, but there isn't,

but they're still getting 50 times more information than they did in the good old days under that simplistic assumption. That's a fair point. Yeah. I know in the interest of time, do you have any thoughts for our final bite? What are you most excited about in the field of technologies over the next five years? The field of technology is a bit too broad. Having seen the first moon launch since my relative childhood the other day is incredibly exciting. I frankly think biotechnology will transform the world in a way that nothing we previously

have done holds a candle. I don't think human beings are going to be running the world at the end of this century. And I think all sorts of other questions, like should we have manned spaceflight or unmanned spaceflight, will dissolve into a doubt about what's a person or what isn't. I guess I think that I'm not so current with contemporary artificial intelligence, but it seems to me clear that computers are going to outthink people in the near future in quite a number of different ways. And so all sorts of things are exciting. Marty, what about you? What are you most excited about over the next five years?

The thing that excites me the most about technology is how it's forcing us to grow up. The real problem is not nuclear weapons. They're a symptom of an underlying problem, which I'll get to in a second. Similarly with cyber attacks, global warming, which has a tremendous public concern. All of those are symptoms of a deeper underlying problem. Technology has given human beings what has traditionally been thought of as God-like physical power. In the Bible, only God was supposed to be able to destroy Sodom and Gomorrah with thunderbolts. We call them nuclear weapons. Only God was supposed to be able to create a flood that would necessitate Noah building an ark. I'm not saying these stories are true, but taking the biblical stories. Whereas technology, climate change is threatening flooding on that level. And so the real problem is not nuclear weapons or

climate change or any of the cyber attacks. It's the chasm between our godlike physical power through technology and our best irresponsible adolescent behavior as a species. And I sometimes liken humanity to a 16-year-old kid with a new driver's license who somehow gets his hands on a 500 horsepower Ferrari. We're either going to grow up really fast or we're going to kill ourselves. And I'm working to make sure that we survive and we grow up really fast rather than killing ourselves. So that's what excites me. That's a wonderful analogy. Thank you so much for sharing that. And this has been an amazing conversation. Thank you both for taking the time to speak with us at ACM ByteCast. Well, you're welcome. And thank you for pulling together your questions. You

obviously did a lot of research on us. ACM ByteCast is a production of the Association for Computing Machinery's Practitioners Board. To learn more about ACM and its activities, visit acm.org. For more information about this and other episodes, please visit our website at learning.acm.org slash B-Y-T-E-c-a-s-t. That's learning.acm.org slash bytecast.