[ad_1]
Blockchain is meant to be safe, but a new paper of quantum computing scientists warns that rapidly advancing quantum technology poses a vulnerability to the much-publicized blockchain.
Blockchain is the technology behind bitcoin. It has been used as a secure digital registration and registration system managed by users, rather than by a central authority. But quantum computers may soon have the ability to break its codes.
"Quantum computers are a risk for any kind of security in which public-key cryptography is involved," Alexander Lvovsky, an experimental physicist at the University of Oxford, told Gizmodo. "However, blockchains are particularly at risk because they are completely anonymous, they are protected only by public-key cryptography, while banks have human tellers, plastic cards and ATMs, you must be a human to use a bank, but you do not have to be human to use the blockchain. "
A computer will translate all the information into a series of single units called bits, which can take one of two values and interact through the rules of logic. Quantum computers are simply a new type of computer computer whose quantum bits, or qubits, can take values between zero and one during computation and interact with all the mathematics of ordinary computers, as well as new operations based on particle physics subatomic. Presumably, these new operations would give quantum computers an advantage over classic computers when it comes to complicated computing tasks such as creating advanced artificial intelligence or modeling chemical interactions. But above all for this conversation, it has the potential crack of widely used public-key cryptography.
Data is normally encrypted by means of unidirectional functions, an operation such that it is easy to combine two inputs but it is difficult to untangle them. Multiplying large prime numbers is an example of a one-way function used in cryptography. Computers can generate code by doing the simple task of multiplying large prime numbers, but computers have trouble breaking down large numbers into prime numbers without having some information about what has happened. One day a quantum computer could easily perform this factoring and make this cryptographic method useless. It is not clear when this quantum progress will happen.
Blockchain relies on these unidirectional functions to create digital signatures that are difficult to falsify for items in the ledger, combining data on the ledger and the new element to be added. But there are no humans to strengthen the defenses. "A blockchain is particularly at risk because the unidirectional functions are the only line of defense: the only protection of the user is the digital signature, while the banking clients are protected by plastic cards. security, identity checks and human cashiers ", authors of the comment published in Nature write.
It is difficult to assess how we should really be worried. Quantum computers are very early, comparable to the electronic tubes of ordinary computers. One advanced enough to execute the Shor algorithm based on factoring and encryption of numbers it may take several decades, but the new algorithms are advancing rapidly, and there have been whispers and articles describing methods that might be able to reverse these one-way functions perhaps in a decade.
"Much like today's [quantum computing] The hardware is not mature, the algorithms that could threaten short-term cryptography are not mature, but they are advancing rapidly, "said Nick Farina, CEO of EeroQ Quantum Hardware, CEO of Quantum Hardware, to Gizmodo. It's panicking, but closely following developments on both sides of quantum computing and looking at post-quantum security a little earlier than you currently think. "
Robert Sutor, vice president of IBM Research, responsible for the IBM Q program, agreed that it is not too early to strengthen security. "Most of all agree that it is wise now to investigate the next generation of cryptographic protocols – indeed, this should be a standard part of the IT security of every organization and data protection operations." , he told Gizmodo.
The solutions are those we have written for a long time: in the short term, scientists are developing secure post-quantum algorithms (unidirectional algorithms that are difficult for both classical and quantum computers) that could be used in the business blockchain. Further on, quantum communications are advancing, from processors to quantum Internet, which may offer new cryptographic technologies.
But it's worth starting early. "The sword is still a question of the future – it does not exist," Lvovsky said. "But the shield already exists."
[via Nature]