In this article, I will examine quantum computers and their potential threats for blockchain projects.
The concept of quantum computers
In 1982, Nobel Prize winner Richard Feynman suggested how a quantum computer would be used in the modern world.
Just a year later, Apple introduced "Apple Liza" – a home computer with a 7.89 MHz processor, 5 MB of hard drive and a floppy drive.
Today we walk with portable devices that are thousands and millions of times more powerful, but our modern computers work in the same simple way, simple mathematics and with the same simple operators. They do it faster and more efficiently, so we forget what happens behind the scenes.
However, so far, despite this development, modern computers can not crack cryptocurrency without the use of vast processing powers.
However, is it true for quantum computers?
To get a better understanding, let's look at the Bitcoin address as the first example.
What is a Bitcoin address?
A bitcoin address is used to send and receive bitcoins. However, it consists of two parts.
A public key that is visible in the general ledger and is required to accept payments and a private key obtained from the public key.
The private key is 256 bits of information in a random sequence. This 256-bit code consists of 64 characters (within 0-9 / a-f) and further compressed into a 52-character code (using RIPEMD-160).
Although many people are talking about Bitcoin encryption, Bitcoin does not use a hashing algorithm.
The bitcoin address "1EHNa6Q4Jz2uvNExL497mE43ikXhwF6kZm" is translated in the private key "5HpHagT65TZzG1PH3CSu63k8DbpvD8s5ip4nEB3kEsreAnchuDf", which is then converted into a 256 bit private key.
Now, to get access to this Bitcoin address, you first need a private address and, secondly, a public address obtained from this private key. Meaning by knowing the private address, you can find the public address.
In addition to this, there is a technically proven theory that, because of this "compression", it is possible to use different private keys / addresses to access the same public key (ie the address). This means that your bitcoin address does not have a private key associated with it, but different, and if someone accidentally finds or hacked one of these, this hacker will have access to all the BTC on this address.
It should be noted that the probability of finding a Bitcoin address with at least some means (or at least used) is minimal, even if it is still possible!
How can a quantum computer pose a threat?
There are two main concepts behind the quantum computer: quantum overlap and entanglement.
The overlap allows a quantum bit (qbit) to be in multiple states simultaneously, and with the help of quantum entanglement, the observer can discover the parameters of a particle at any position in the universe. universe. The connection is maintained, even if they are moved to different parts of the Universe.
In essence, a quantum computer can process and analyze an infinity of information at the same time – and so quickly and differently than the human mind can not grasp it.
How can you protect yourself?
Of course, the best option is to sit back and watch how Bitcoin and other blockchains introduce new cryptographic features to protect against potential threats from quantum computers, but it takes time and this process can be lengthy in terms of scaling.
Another option that can be implemented is to use the blockchain address only once to send a transaction. When quantum computers attack Bitcoin (and other cryptocurrencies), their first goal will target those who have outbound transactions on the blockchain, which contains assets.
This is because when the computer tries to crack the bitcoin address, the starting point is when the transaction becomes public. In other words, this happens when a transaction is "registered" for the first time – this digital signature, which is formed by a private key and confirms the transaction within the network. Compared to conventional computers, quantum computers could quickly process this information.
Initially, Bitcoin Core software can provide a certain level of security because it uses only one address and then sends the rest of the funds (if any) to another address in the pool. However, third-party portfolios may use the address multiple times for outbound transactions. For example, this can be a big problem for users who accept donations (unless they update their address every time they withdraw funds from there). The biggest disadvantage of Bitcoin Core software is the amount of space required on the hard disk as well as the careful saving of the updated copies of the entire blockchain. However, as quantum computers evolve, they will inevitably turn SHA256 into a significant vulnerability, and although this is one of the first hashing algorithms hacked by quantum computers, it will not be the last!
The developers in the cryptographic space are fully aware of the threats of quantum computers and there are several projects that want to create blockchain resistant to quantum phenomena, although at the moment the main focus is on other blockchain issues such as scalability and speed of transactions.
Featured image courtesy of Shutterstock.