The national Institute of standards and technology (NIST) presented the results of the second round of standardization of protocols postkantoor cryptography, where the allocated algorithm on lattices. It is both potentially suitable for large-scale deployment and quantum-resistant. The report published on the NIST website.
The quantum computer of interest to researchers not only because it can simulate a complex physical system, but also because he can crack a cryptography protocols. The algorithm of Shor, for example, are able to hack a very popular cryptographic algorithm RSA. One of the ways to protect against quantum computer is to change the Protocol encryption by going to quantum cryptography, in which to transmit information using quantum systems. The problem of transition is that you need to change the encryption at the physical level. The other way is polcanova cryptography, which uses the classical system and the task, but so complex that they are unable to solve even a quantum computer.
Last year, Google first decided task, inaccessible to conventional supercomputer, but it is very far from breaking cryptographic systems. Moreover, quantum computers will require more than one year to reach the level, when you can hack at least the old system, which uses weak cryptography. However, it is important to understand that as soon as a quantum computer, it will be too late to change the cryptography, so standardization of new protocols is now.
In 2016, the American national Institute of standards and technology launched a competition in which various research centers have developed methods of quantum-resistant cryptography. The results of the competition, which aims to develop an encryption standard to be announced in 2022, but already now it became known that among the proposed approaches there was a favorite: postanova cryptography lattices.
This approach is based on problem of discrete optimization, namely finding the shortest path on a multidimensional lattice. While other tasks of discrete optimization, such as the decomposition of large numbers into their Prime factors, are solved by a quantum computer in polynomial time, to date there is no known quantum algorithm that can solve the problem on the grid in less than exponential.
Of course, there are many tasks where a quantum computer does not provide benefits, but for the full-scale transition, you must implement a solution that is easy to implement in modern cryptographic systems. Though the search paths on the lattice an incredibly difficult problem, with it you can quickly generate a secure key. Moreover, the process of generation not consumed a lot of memory, for small low-power devices.
About what is the status of a universal quantum computer, read our article “one of the qubits is more”, and read more about quantum cryptography you can read in the material “Quantum technologies”.