 And another author of this presentation is Sunjir Kim. In this presentation, we prepared together, but only I speak. The title is Blockchain for Cyber Defense, and it would be good as you think, is our topic. It's 5 AM in Korea, so I think the condition is not normal, but I hope you understand for, understand. So again, I'm Sunjir, and I'm a PhD student in Korea University, captain of the Republic of Korea and Army. I have three years experience as a researcher in the Agency for Defense Development. It's about development of defense and arm system. As a security researcher, I'm interested in network security and cyber defense and blockchain. About blockchain, I was a speaker of CryBlog 2019 at IEEE Infocom. Title was Contouring Block Rederting Attack Efficiently. Also, I speak at CryBlog 2020 at ACM Mobicom. The title will be a little bit September, and title will be Procival of Stake Hashtag Predatory Distractive Ategon. Procival of Stake Cryptocurrency is it will be about novel attack methodology about POS cryptocurrency. And not about research. I like to get groundbreaking ideas from philosophy, and my favorite first are Degida Nietzsche Foucault and Wittgenstein. Another author of this presentation is Sungjook Kim. He's my advisor and he's a professor of cyber security in Korea University. And he's a revivered in several international hacking conferences like Blackhead Asia and the Queen's Side. And he's also advisor of an undergraduate hacking class, Cycler. This group, the hacking group Cycler, is now competing in DAFCon online. And his main research areas are focusing on trustworthy system developments, methodology as SDSC, secure SDSC and RMF, common criteria, CMBP and blockchain, and et cetera. So our topics are what is blockchain for cyber defense? Maybe many of you are a blockchain professional, but not familiar with cyber defense or blockchain for cyber defense. And our main discussions are challenges for block challenges in cyber defense and then we will talk about related military projection analysis. And as a summary, we will talk about takeaway. Targets of this talk are four kinds of people. Someone interested in blockchain and someone interested in cyber defense and someone interested in how blockchain can be hacked. And someone who needs fresh ideas, who doesn't know blockchain or what is cyber defense, I hope this talk will give you fresh ideas about this topic or any ideas. So blockchain for cyber defense, what is it? Maybe you know what is blockchain? Actually, blockchain is not clearly defined. Blockchain is started from Bitcoin, founded by Satoshi Nakamoto. In his fight paper, he didn't talk about what is, didn't write clear definition of blockchain, but his main topic was Bitcoin. So in my search, I think blockchain is constructed by three concepts. Maybe some can think differently because the start of blockchain was not clearly defined. So one is as a data structure has changed blocks and as a network structure distributed network and as a consensus structure decentralized consensus. And it has some nature problem, kind of fundamental problems. It's called trial and error scalability, security and decentralized decision. Three kinds of characteristics can be satisfied at the same time. Then what is cyber defense? Maybe some of you know, but maybe a majority of you don't know. This picture is just for fun. It's not like cyber defense. It's just funny. So what is cyber defense? Before I talk about this, I should define what is cyber security. Classically, many people talk about information security, also many people just talk about cyber security like information security. If cyber security is the same as information security, then it's not worth to talk about cyber security or name cyber security. So I bring a clear and distinguishable definition from the reference at the bottom you can see. So in their research, they define cyber security as treating stress using ICT. Then what is classical information security? Information security is treating stress to information-based assets, but cyber security is treating any stress using ICT. So ICT is information and communication technology. For example, car accident is not about not included in information security, but if car accident is by a car remotely controlled by a hacker, then it is included in cyber security domain. So now we can define what is cyber defense. So cyber defense is intersection of cyber security and national security or national defense. National security and national defense or national defense are just used in same way many times. So just narrowly, cyber defense is about military defense, but widely it's all about national security. So why is it like that? So you can see in the picture, at the past the stress to countries was worse through only military domain. They should overcome armed force and army, air force and navy. But so general physical stress on defense choose through military area, but non-military domain, including severe access and critical infrastructures are covered by our military domain. But these days, they can be attacked directly by ICT, information and communication technologies. For example, they can just hack the plant and hack the financial systems and hack government information systems. It's already happened. 2007 cyber attack to Estonia was really severe. That's the beginning of the CCT-COE in NATO. And 2010, Stuxnet to Iranian nuclear facilities, it was shocking accident that computer virus can stop the nuclear targets and stop nuclear plant. And 2015, Black Energy template stopped the Ukrainian power grid. So now cyber attacks can directly attack the national security and national assets. So therefore, national countries need powerful cybersecurity technologies. So that's how cyber defense meets blockchain. Well, blockchain looks secure and reliable. Many articles and many news always talk about it's really nice, secure words with blockchain, like secure, reliable, survival, and so on. So it's true. Blockchain technology provides, it's not about single point of failure and it's immune to any minority attacks. And even the DDoS attacks are really difficult to blockchain. It should overcome majority resources. So policy makers of countries easily think like that. Defense systems require high security and security and high reliability of blockchain. Blockchain looks unhackable. OK, then defense needs this technology. It's really simple, again, expectable. In reality, many projects are always already in progress. We will discuss about related projects at the next section, but in preview, military includes a messaging app built on blockchain. Blockchain supply chain enhancement for trust and assured FPGA and ASICS, decentralized key management using blockchain, Army Innovation Network, provenance using blockchain and disconnecting networks, Navy, multi-multi-factor authentication, CUPS through resilient blockchain framework, Chinese surgery, or storage system using cryptocurrency. Blockchain-based, recording intelligence, French military police record on Tadus blockchain, South Korean military. Blockchain-based digital identification, DID, and also other projects. So will it be as good as you think? Well, in this talk, I want to question and introduce some challenges. So to meet the challenges, let's go to the battleground. Maybe some of you like this game. So what is waiting for us in the battleground? There's a profession. I entered a profession, Carphone Kloswitz, and he's a really professional in war and battleground. He said in Twitter, war is volume of uncertainty, three quarters of the vector zone, which action in war is based on, based on wrapped in a fog of a greater and lesser uncertainty. In summary, he says, it's full of uncertainty. So what is big uncertainty? Blockchain technology already assumes many uncertain situations, right? So, but in battleground, uncertainty can be really extreme. For example, you got ordered to go to a mountain and save the mountains. In Korea, mountains are like that. And we have, our territory is covered by, our 70 of territory is covered by mountains like that. So when you got ordered to go to mountain and then we expect mountains are covered by trees usually, right? But in reality, mountains can be just like devastated in, just you can go to mountain and there can be even no single tree, where trees they're burnt down a year ago. In Korean war, at 1950, most of our trees were just burnt down, yeah. So what I want to say is, situations in battleground can be extremely measurable. But you got ordered and then just you should say, I, I serve in army. So let's assume policy makers said, adopt the blockchain technology and secure our netters. And you also let's assume it's not questionable. You don't, you're not allowed to question about this decision. Even though many, actually many people can be, can don't agree with private blockchain networks, but yeah. So we will encounter three challenges. Challenge one, air gap networks and challenge two, first dynamic environment. And challenge three, the resource shortage. So challenge one, air gap netters. So what is the air gap netters? This is maybe familiar for most of you. In military domain, networks and critical infrastructures in of country, many networks are have air gap environments. Air gap is something technology to make netters isolated. So you can see internet, mainly stress are come from other internet. So to protect internet, you can make air gaps. Air gaps can be soft air-based air gap and how do you base the air gap? And there's true air gap, true air gap, true air gap means there's no communication between air gap. But well, it's not always magical because stuff's not exploded air gap netters anyway. If there is net air gap anyway, if there is air gap, then it is hard to make construct blockchain because just communication is not possible and many networks are partitioned and isolated. So anyway, let's make blockchain adhere. So for example, you can construct servers of each party is isolated networks and communicate messages by those servers. Then it'll be single point of failure and it's just centralized. Another way you can make just isolated netters and each isolated netters has isolated blockchain. But then the isolated netters has not enough nodes or not enough servers to make enough decentralized network. So it'll make decentralization not effective. So in summary, because of the air gap structure of defense network, it may be hard to adopt blockchain. Second challenge, first dynamic environment. Wherever the military goes, communication must always exist. In actually it was same at the past warfare but in modern warfare, getting information and processing information and make decisions are really important and should be fast because we should make decisions faster than enemy and move faster than enemy so that we can make the superior position. So anyway, two for that for this process, communication must be followed. So in this picture, in modern warfare, all of these things require communication. So it means, let's see the example. It's map of word or second and it's map of word second map is how Nachi extended their occupied territory really fast and broadly and right map is how their occupied territory is showing to really fast. Let's see the second left map. When Nachi extended their occupied territory, then communication system must follow all of occupied territory and cover their communication really fast. Even if their advance is really fast, communication and their system must follow there's no exception. At the last right map, even if their territory occupied territory sharing to really fast, communication system will sharing really fast anyway, just whatever is distributed throughout. Anyway, another example, it's our country case. It's about it's map of Korean War in 1950. It's entirely just before the warfare, before Korean War, the territory was divided at this line, 38 parallel. But just in three months, South Korea's territory was sharing to just two cities, Daegu and Busan and we are really sharing to really fast and but you can see just in two or three months we expanded our territory till the just nearly end of North Korea, but we retreated really fast again. What I want to say is background environment is really dynamic and we can't choose and there's no exception and we are just first in we are just first to meet situations. So let's see this, let's move on the blockchain. So let's consider the case Southern expansion and it's our private network, blockchain network is just like PBFT then we have at the left situation we have eight total nodes and accept over 14 nodes are like two, but we expanded our territory really fast and we just added a lot of nodes because we should follow the, we should cover the occupied territory and then accept over 13 nodes should be 12 but in PBFT here it is kind this kind of consensus mechanism we need settings but if this expansion is really fast and this setting can't be if this setting is not adapted then it'll be really easy to make consensus. The past majority becomes minority, eight is minority of 36 so that is now your minority can make consensus. Another case is kind of a reverse case. Let's think about Southern Shearing Kit. Shearing Kit is this tackle. Your original set is total nodes 36 and it's in PBFT accept over 13 nodes or the number of accept over 14 nodes is 11 but most of nodes are just destroyed and then you have to turn those eight and accept the number of accept over 14 nodes should be three but you're just destroyed so you can't make setting in the time but so it will be nearly impossible to make consensus. So the past minority becomes the majority in this situation that is now your majority can't make the consensus. So another situation bombing and partitioning. It's the last situation your nodes just can be partitioned in public blockchain it's nearly impossible because nodes are connected by like a worldwide web just so it's really hard to make clear partition, just divide into two partitions but it's possible in war situations. So for example you have to turn a 36 nodes and it's partitioned and there's no measure to anymore. For the murder there's another issue. If you connect the partitions but they have their own blocks and especially for PBFT here deterministic consensus mechanisms consistency will be really big problem. So we'll meet our first problem and in this situation we can't just steal another information we can't choose just one information which we need collect all information and process and decide so it'll be a problem. So it was a second challenge to summarize in more extreme situations assumptions can be easily broken and weakness can be easily revealed. So especially in my examples deterministic consensus mechanisms that cannot guarantee aliveness are really problems in these situations. Challenges research shortage is actually it's a classical problem of blockchain but I can't miss this problem. I can't just, I can't mention this problem. Blockchain's other name is state replication system. So it will replicate computation research, storage research, latency research, bandwidth research. But existing military system were consistent considered existing missions and existing systems. So just replicating existing performances will be a problem and we adopt blockchain for missions not missions for a blockchain. So influence on mission critical functions should be checked. Mission critical functions should be guaranteed and then we can adopt blockchain. But yeah, first problem is research consumption. Then what is the second problem? Second problem is serving research consumption is not easy. So if we don't have enough research then we should get more resources and then we need to get another more systems or more resources than we need to use defense acquisition process. So, but maybe some of you already knew but military acquisition system is, process is really conservative and it requires really a rigorous task and evaluation process. It's really heavy and defense acquisition process is was having developed in this way. So you can see in the left picture is the US military acquisition system and it's really bureaucratic and conservative and really heavy. So there are many articles or interviews that DOD or many countries are suffering from full defense acquisition process. And it's all well rigorous tasks and evaluations and rigorous acquisition system process is essential but it is a really big problem in cybersecurity because system is developed and vulnerable abilities are always hiding. Hiding but vulnerable abilities are just found time by time but military acquisition system is not that rapid to react from this updates or kind of that. So anyway, military bureaucratic acquisition system process is not, it will be difficult because of that it will be difficult to serve research consumption problem. So in this situation what can you do? Proof of work to adopt proof of work or we can't waste energy, of course, profile stake, we don't have coins in defense system. Then when you go to private consensus mechanism like PBAPT then we will go back to the challenge to again. It can't guarantee livening so it will make such extreme problems. So in summary, mission is always first but due to the military environment support is not so timely and sufficient to adopt blockchain. So next is related military projects. So we surveyed 42 defense projects about blockchain and categorized as below. And its project can be categorized into multiple categories. For example, there's a research about identity, key management about a military drone system then it's categorized into internal things and communications and identification, authentication, yeah. And especially data integrity category is just for data integrity project. It's because actually adopting blockchain technology is basically about data integrity. So we categorized a project only about data integrity into that category. So main categories are like that, data integrity, supply chain management, internet of things and communications and identification and authentication. So, so we are someone careful about mentioning a project because about related project, project detailed information about many rear military projects are classified. We got information from even just project notification and interviews and just use articles. So the information we got is can be not clear or can be somewhat misunderstood. So we want to notice that our comments are based on limited information. So data integrity, for example, there are three projects. French military police records and taxes blockchain. It's interesting that they put records on public blockchain. So maybe they can avoid problems that I mentioned like the problems happened in private blockchain. And another example is U.S. DOD project, sharing of defense research development testing evaluation on blockchain. And another project is also U.S. DOD provenance using blockchain on disconnected networks. This project is also interesting that they already considered some disconnected network situation in tactical netters. So another related category is supply chain management. In cyber defense supply chain management is really a big issue. Maybe you read Bloomberg article about microchip hacking, but I don't know if it's true or not, but what I know is it was a truly a big issue and there are other articles about supply chain attacks or suspicious and yeah, it's truly a really important attack vector and so there's a U.S. DOD project about it, blockchain supply chain enhancements for trusted and assured RPG and ethics. But blockchain and supply management is actively researching for efficiency of a supply chain not only for security. Another category is internet of things. There's a U.S. Department of Homeland Security project is combining blockchain technology with critical infrastructure. This project is about sensors and cameras that protect data so sensors and cameras protect integrity and authenticity of critical infrastructure. So this project is about IOT, so we can just relate it to challenges through research series, but I think the infrastructure is not dynamic so it can be adaptable, I think. So in communication category, there's a DARPA project building on encrypted message system based on blockchain technology. I think it's about tactical network so I don't know it's detailed information but if it is related to messages in tactical networks, challenge two for dynamic environments and challenge three research shortage should be considered, maybe they were considered. For identification and authentication, there are two projects, for example, USDHS project decentralized K management using blockchain and there's our country project, South Korea project blockchain based DID. But maybe some of you noticed some of these projects are not domain specific. I mean, it's not just for only for cyber defense, many projects are just general, like especially identification and authentication, the decentralized K management and DID is not only military issue, not only cyber defense, so maybe they are not interesting. So related projects in my example are like that. So lines mean that projects, I think, is not domain specific. So I'm interested in domain specific blockchain first, blockchain specifically for cyber defense. So I'm still surveying about this topic and I'm preparing a paper. Then actually, I think I criticized a lot with just question this topic and introduce challenges but then some can ask, then what are alternatives? So what I want to say is, we don't need to choose a perfect blockchain structure. As I mentioned at the first part of this talk, blockchain is structured by three concepts. As a data structure has chain blocks and as a network structure distributed network and as a consensus structure decentralized consensus. But you can just give up one concept or two concepts. Just maybe you only need distributed network and parallelized network. So what I need to do is figure out problems and figure out right solutions, not just decide to use blockchain and figure out which blockchain is adaptable. So to summarize, take away are three. Cyber defense makes more challenges and requirements for blockchain. Air gaps, sudden expansion, sharing keys, partitioning. Extreme situation can exist. Second, blockchain's resource consumption can be a problem but defense environments are not that flexible to assign more enough resources. And third, we don't need to cling to blockchain if it's not adaptable. Otherwise, it will bring more issues. So it's all of my talk and get in touch to this emails. These emails will outcome any questions and discussions. I think this presentation will be uploaded on somewhere so you can see our emails anyway. So thank you for your attention and thank you again. Any questions? Is there a question? If you can't ask now, then you can just send email or send message to this code. Any questions and discussions are welcome. Thank you. Then I can just quit the live streaming, right?