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Is Quantum Computer Really a Disaster for the Crypto World? So what’s the solution?
Many people probably have heard that “Quantum Computers” are an upcoming threat to the Crypto industry. However, some people may still be confused about how Quantum Computers can pose a threat to the Crypto world, so today, Siam Blockchain is here. Help everyone learn some misconceptions about quantum computers along the way.
How good is a quantum computer?
A professor specializing in applied cryptography. Described in a blog post that “The general description of a quantum computer is the same as that of a conventional computer,” but instead of having bits of 1s or 0s, quantum computers have quantum bits that can be both 1s and 0s at the same time. Thus, a quantum computer can compute all possible values of its input at the same time.
This ability affects encryption. Because cryptography, signatures, or anything else that generates cryptographically is the same as crypto wallets, quantum computers can try all possible keys at once. And then it can break all types of encryption.
but in reality Quantum computers are more complex than anyone thinks. And it’s too inefficient to do that. Because although it has the ability to surpass the general computer. And it works in parallel. But at the same time, it is very limited in its ability. Therefore, human beings will be able to take advantage of quantum computing only if we are solving the structural problems of quantum computing.
How does a quantum computer work?
Quantum computers have quantum algorithms that can solve certain problems faster than the best algorithms on conventional computers. But in addition to these algorithms Quantum computers do not have any of the advantages or superpowers most people talk about today.
Shor’s algorithm: This is why people around the world think Quantum computers can pose a threat to the crypto world, as Shor’s algorithm is a quantum algorithm that can break cryptographic algorithms based on factoring or discrete logarithm problems, including RSA, DSA, ECDSA, and DSS.
I believe that many people would feel familiar with these names. Because all of the above are what people around the world believe to be “99% safe” today, and these are almost 100% related to blockchain and the internet in general. that but all of these It is considered to be quite an amazing ability.
Grover’s algorithm: This is slightly more unique than the above algorithm, because Grover’s algorithm is a quantum algorithm that can attack anything at the sqrt(N) stage instead of the normal N stage, trying all possible keys to Access what is encrypted.
Stage N attacks are common attacks in all cryptographic forms. But sqrt(N) rank attacks weren’t that powerful. Because this type of attack is to halve the size of the actual key.
In fact, the key we’re using is already quite large. So a sqrt(N) attack would take longer than the life of the universe to break the existing password. Moreover There is also recent research showing that Grover’s algorithm is even less effective in practice than we thought. So about using quantum computers to break encryption. So it’s not a big thing for us to worry about.
Although Shor’s algorithm for quantum computers is extremely powerful, But it’s good luck for us. Because it seems that humans are still far from being able to use it. And more engineering efforts will be required to develop a quantum computer.
Will Quantum Computers Affect Blockchain?
Imagine that we have a functional and scalable quantum computer. Shor’s algorithm can be run on normal-sized RSA, DSA, etc. keys. So what if this is released to the blockchain world?
The big problem now seems to be that anyone can access a crypto wallet’s public key and quickly calculate the private key with Shor’s algorithm. This will give quantum computer owners access to any wallet they want. and stole all the coins in that wallet.
If such an event occurs It could become the thing that will cause the price of all cryptocurrencies to collapse immediately as Crypto will become unreliable anymore. And it will certainly destroy the digital currency as we know it today.
Sounds very scary right? But as mentioned before, quantum computers are not that powerful because Hash functions are not vulnerable to quantum attacks and Proof-of-work. It will continue to work perfectly. In addition, quantum computers cannot mine Crypto as well, therefore cannot occupy the network. like many people think
And what about the effect on the wallet? Fortunately, there are many people on our planet who are good at post-quantum signature patterns. (post-quantum signature schemes) which can be used to replace broken ones Because these are based on hard problems, not factorization or logarithm separation, it’s reasonable to believe that no quantum algorithm can break them.
So if we want a secure blockchain from quantum computers, there are two ways.
- Start a new blockchain with post-quantum signature schemes.
- Move existing blockchains to new post-quantum signature schemes.
Quantum computers are a real threat. But quantum computers are not magic. So it can’t break all encryption. And it won’t be a disaster for the crypto world, because we now have a new type of encryption that is resistant to quantum computers. And it’s being used already.
Source: Reddit
