What is the influence of quantum computing on the security of the bitcoin blockchain and other decentralized networks? In theory, quantum computing can pose a serious risk for cryptography because they can decrypt encryption. Consider, for example, the public keys (addresses) of your bitcoin wallet.
Quantum technology continues to evolve and it is a matter of time before it is accessible to a wider audience.
Crypto currency and security
Is crypto currency also at risk? Bitcoin and other block chains are basically dependent on encryption and encryption.
Behind every public key (address) is a private key, a secret number that gives you access to your currency. Most crypto currencies use elliptic curve cryptography, which in fact makes it impossible to derive a private key from a public key.
Elliptical curve cryptography (ECC) is a form of public key encryption. All public key encryption is based on the idea that the encrypted data can be cracked. As long as the key needed to make the data available remains secret. This requires an algorithm that works one way (encrypting) easily, and the other way (decrypting) is very difficult.
But quantum computers have access to advanced computing power that can potentially extract private keys very quickly from the public keys, at least for the most common encryption schemes.
The keys can be protected. In the future, crypto coins may integrate Lamport signature, this must offer quantum resistance. That affects the size of the blockchain blocks.
A Lamport signature is a method in cryptography to construct a digital signature, developed by and named after Leslie Lamport. This allows checking of an incoming file. Lamport signatures are very difficult to crack, because each Lamport key can only be used for one message (Source: Wikipedia)
Ethereum, bitcoin and altcoins
Ethereum is planning to add Lamport signature as an option in version 2.0 or Ethereum ‘ Serenity ‘.
Bitcoin developers do not yet have any fixed plans for Lamport singature, but it is on the table. Because quantum algorithms require a digital signature to crack an address, you can only use each address once.
This topic is important for older crypto currencies, but a number of (newer) smaller crypto coins have been working on quantum resistance right from the start. Many quantum-resistant algorithms already exist, such as XMSS, Keccack and Winternitz, these are applied by projects such as QRL, Hcash and IOTA .
Although quantum-resistant schemes are difficult to break, they are not difficult to implement. Blockchain developers do not need a quantum computer to develop a durable encryption scheme.
Crypto currency miners also come into contact with cryptography. They said they use large amounts of computing power to solve cryptographic puzzles. In exchange for solving the puzzle, the miner receives a block reward.
The fact that countless miners provide the network means that Bitcoin is a decentralized network. For a single miner it is difficult to dominate the Bitcoin network. But if one miner gets access to a quantum computer, he can reach a huge hash speed and thus dominate the Bitcoin network.
For example, the network may be exposed to a 51% attack . This is not currently considered a serious problem.
As long as several miners have access to a quantum computer, no quantum computer will gain power over the network. Alternative proof-of-work methods can prevent so-called quantum dominance. Also, ASIC devices that are already faster than normal computers will reduce the quantum advantage.
Crypto coins have time to prepare for quantum threats. Most experts believe that quantum computers will begin to break through coding schemes within the next five to ten years. This is not a lot of time, but should be enough to prepare.
Google and Cloudflare
Crypto currency is only a small niche of the technical world, researchers are working elsewhere on post-quantum security solutions.
Google and Cloudflare, for example, have collaborated to experiment with quantum-safe algorithms. The aim is to improve internet security, but it is not clear whether this will particularly benefit decentralized technology and crypto coins.
Interview with Liu Jin, ABCMint
Also watch the ABCMint Foundation interview with Liu Jin. He supports the proposition that bitcoin is at risk due to quantum computing.