This bitcoin-like Cryptocurrencies has recently captured the imagination of the public. They provide an exciting alternative to traditional the monetary systems. This bitcoin transaction is essentially a series of publicly archived puzzles on Blockchain. These puzzles used to protect bitcoin are so complex that its current computer technology is not powerful enough to crack them. Here's how it can be with your bitcoin. But quantum computers can break these puzzles in decades to come.
How does encryption work behind this bitcoin?
Traditional currencies rely on dependent intermediaries such as banks to verify and record all monetary transactions. The cryptocurrency economy depends on the public account holder - blockchain - which is maintained by all the honest participants of the Bitcoin network.
Banks are usually required by law to certify the sender and recipient of any transaction. But Cryptocurrencies transactions, in theory, can be done anonymously.
Imagine an approximate potential bitcoin recipient named Alice. First of all it should create a unique and extremely difficult puzzle which can be easily solved using only a secret signal (called a private key), which it keeps on itself. In addition, it should be easy to verify that the solution is correct. This is done using another signal (called the public key). After this happens, Alice sends the puzzle to anyone who wants to send him a bitcoin.
Now imagine a sender; let’s call him Bob.
If Bob wants to send Alice to Bitcoin, he will deposit a transaction on that network which includes two components: Alice's puzzle and the solution to solve a puzzle unlocking the money sent to Bob in previous transactions. He will also reveal the public key to be used to confirm the solution. If the solution is verified by various participants of the network, they will assume that Bob is actually authorized to spend his bitcoin and accept the transaction in blockchain. Alice can now spend money by revealing the solution to her puzzle.
In this way, the whole account of the Bitcoin transaction is completely public, while the identity of the Bitcoin owners is secure.
How can you access bitcoin without the private key?
In fact, anyone who can solve any of the puzzles on blockchain without a secret hint can access the stored money. Therefore, the only specific feature of the recipients is that they can solve these puzzles more efficiently than others, only thanks to the secret hint.
Most of the puzzles used for bitcoin take the form of signatures. That is, bitcoin transactions are signed electronically using complex algorithms, which the mathematicians call the oval curve. The idea is that making such a signature is prohibited for any computer as long as no secret key is kept, and it can be easily verified using the public key.
However, these signatures really seem impossible for imitation of today's computers; Quantum computers can potentially solve them very efficiently. This is possible because quantum computers are not restricted to processing digital information, but calculate directly using quantum mechanical interactions that dominate physics on a microscopic scale.
Researchers are still trying to figure out what kind of problems is better at solving quantum computers. But we know that today's cryptography has two inherent problems, that tomorrow's Quantum computer may be capable of resolving efficiently, it is for experts at home, in addition to solving oval curves, the other problem is main the factors are looking for a number
In particular, oval curve cryptography can be broken into a version of the noise algorithm. This algorithm is able to calculate the secret key from the public key, and thus the public key is capable of making signatures immediately after it appears. This cannot be used today's computers. In fact, we believe that only quantum computers will be able to do this calculation.
How to steal a thief bitcoin with a quantum computer?
These existing mechanics of Bitcoin mean that the public key only appears with the signature when the transaction is proposed on the network. Therefore, to calculate the private key from the public key, there is a very small window of opportunity for quantum computers and offers optional sign-up transactions, for example, Bob's money goes to the thieves instead of Alice.
They can think of this attack that it is like looting the customer before entering the bank to deposit the money. To make things even worse for its bitcoin transactions, the public key is actually already known and stored on Blockchain. It removes the barrier of time for the above attack and allows the thief to steal money even if no transaction is proposed.
This bitcoin affects about a third of the market capitalization or several decades of billions of dollars. This is like a traditional bank theft where the thief does not have to wait for the customer to make a transaction. It is difficult to estimate that quantum computers will be strong and they will be fast enough to do these attacks, but it is reasonable to believe that we are at least safe for the next ten years.
How can we protect bitcoins?
It is important that researchers have alternatives to oval curve cryptography which are resistant to attacks by quantum computers. These conversations and even though no standard has yet emerged, alternative cryptocurrencies that take quantum computers into account are still being developed. So if bitcoin can ultimately kill quantum computers, blockchain and cryptocurrencies will definitely be.