From Classical to Quantum-Safe: Upgrading Blockchain Security for the Next Era

My name is Salvazor Miao. I'm from Namrial and today I've come to you with this talk about an idea on how to upgrade the blockchain into a quantum safe one. In this talk we will start from the very basic information about quantum computing for those of you who don't know. Then we will lean forward about what are the current vulnerabilities of existing blockchain and then we will lean on how Nami is going to work on these type of things. So first of all Namir just want to talk about this kind of topic that's because our main operational main purposes are done via current encryption like RSA ACC etc etc then in this talk we are just going to introduction to quantum computing then the current vulnerabilities solution and our solution so let's start the first thing that I want to show you that I want to talk to you it is what is quantum computing and what are quantum computers.

So just to be uh clear just to be easy quantum computing is just a computational paradigm that uses the principle of quantum mechanics such as the entanglement or superposition in order to elevate the computational power to an exponential level. when the world start talking about quantum computers in 1980s the first idea emerged from Richard Fayman and later the Peter Peter Shaw in 1994 developed an algorithm capable of breaking current cryptography algorithm. So just to understand why quantum computer is so much powerful than normal computer at the base there is the quantum bit the cubit the in the classical type of way that things are done in our computer we have the bit that are or zero or one that can be in only two state in in the case of quantum computers we have zero one or a combination of those type of state in In order to elevate our computational power, we we uses even the properties of quantum mechanics such as the entanglement or the superposition. So in order to give you some sort of idea how powerful it is a quantum computer in like maybe five years, 10 years, we could expect to break RSA in just a few hours. And this is such a really really bad things for our company or in general for those companies that work in the classical way that encryption is made.

So anything encrypted today with RSA or ACC can be archived and then cracked once a full tolerant quantum computer exist or when it gain certain maturity. So just to uh give you some number about how the world is moving forward and towards quantum computing. There are several industries, several companies, several countries that are now investing in those sort of things. For example, China, Russia, France, Europe, United Kingdom, Canada, America, etc. and even some big tech like EBM Microsoft with a project mayorana one that is a quantum sip that could have some of the revolutional new class of material etc.

Google right now is working in quantum AI that is really really important quantum AI is just the combination of quantum capabilities with AI and then AWS with the cu cloud quantum computing via Amazon bracket. So let's now dive into the main things of this talk. So how a quantum computer could break our blockchain. So I already I understand that you already know what are the current vulnerabilities of blockchain and we we have a short amount of time so I will not go dive deep into that. So there are 51% attack, contract logic bugs, private key and wallet compromise, chain bridge exploit, etc.

, etc. But the real thing is how a quantum computer could break the blockchain. The first thing that comes in our mind is the shorts algorithm. As I said before, shorts could be used in order to break current cryptography. That's because it can solve logarithmic problems in a polomial time which is currently unfeasible even for the most p powerful computer.

The second things is the Groover's algorithm. The Groover's algorithm is just a speed up a quadratic speed up hash search on our system. So it could easily break proof of work or proof of stake giving a majority power without having the 51% resources of the blockchain. The last things the last threat that we want to talk is the harvest now decrypt later. This is just a paradigm of mind where some sort of malicious sector could achieve all our transaction all our information on on the internet on the web three right now and then later in the time as I said before could break those type of encryption and then gain access to our information.

Then every used address is already exposed exposed because if you can take the private key or the public key of a certain type of transaction, you could get all the information about this type of transaction and then with the private key you can fally sign some type of transaction in order to steal our cryptocurrency. So why so why quantum computers have not broken our security system and that's because quantum computers have some real problem right now. The first problem is the fragile cubits things. These type of things is that even a small amount of disturbances quantum noise can cause this cubit to lose their quantum properties. There is this uh this draw that I really appreciate that is the quantum coherences.

The quantum coences is just a sort that a cubit doesn't know where to go. It doesn't know their properties their values. So even if we do some sort of operation, some sort of calculation we arrive to a different comp results. The second things is the huge overhead for for full tolerance quantum computer. That's because we need at least 1,000 physical cubit in order to get one logical cubit.

Right now in the research area of quantum computers, these type of things can be achieved in less than 1,000 cubit. But in order in a realistic world in order to break RSA we at least need millions of physical cubit. I know there is the surface code definition there is the infrastructure the laser the laser one. So it's not like maybe an impossible things to reach this type of computational power. The last thing is the error correction.

As I said before the cubit are very fragile. So quantum computers need this sort of error correction code to resolve some of the serious problem. So there are several solution to quantum computer attacks right now. There are two main road ahead. The first road is postquantum cryptography.

That is the simplest one out of the two because it's just a paradigm that will need to replace RSA or HDSA with algorithm that are safe from quantum computer attacks. That's because this type of algorithm are based on mathematical problem even difficult for quantum computers like the less based one the ashbased one the codebase one or multivariant cryptography. The second the second road is the quantum cryptography itself. So if you cannot defeat them join them in a sort of way. So we like to apply quantum mechanics principle like the QKD or some other things of protocol like the BB84 in order to encrypt our information with quantum computers.

In this way we are safe from the attack of quantum computers because we could protect our ourselves. So just to give you some sort of background on why postquantum cryptography is so important right now even the European Union and the east are working on a road map to migration to the in order to give the the data that are right now in the internet a bit of security. So how are we going to implement pico in blockchain? There are three road that we can follow. The first is an hybrid approach where we combine cryptography algorithm, classical cryptography algorithm with postquantum cryptography.

The second one is a blockchain fork, an hard fork of the blockchain where we create a new version of the blockchain that only uses postquantum cryptography algorithm and then the protocol update. There are some problems with this sort of solution. The fact is the keys and the certificate that uses postquantum cryptography for example the lithium 2 the lithium 3 algorithm have key and certificate that are even larger than the one that we use right now and this could affect transaction speed and blockchain size. So our solution is a simple one. It is a mocked one.

Right now we are testing some other roads that we can take, some other things that we can understand and this is just to build a signature on top of an Ethereum transaction. This type of things is done via generating the hash of a transaction then generate a private key using postquantum algorithm. For example, as I said before, Falcon or the lithium 2 tree, Denise is recommending to use the lithium tree as the postquantum cryptography algorithm. Then we generate the signature and then we can take those signature on the chain and be safe from the attacker that tries to take our personal information on the information of our transaction. The use case for our demonstrator is just some sort of testing.

We right now are not trying to imp implement it on the chain itself but we are studying how it can be possible to protect ourselves in the future and right now. So I would like to thanks all of you for the attention. Sorry if my English is bad. It's not my first language. If you want to contact me uh there is the link in link and the mail.

Thank you everyone. [Applause]