Hello, my Cheshire cats🐈‍⬛🎩

While writing big posts I wanted to make a small introductory about post-quantum cryptography🧬

Of course I will attach collection of materials (there will be detailed information about algorithms, cryptography itself and even attacks). 

Start with what it is and why we need it 🙃

The progress is going on very fast now, and very soon (in 10 years) quantum computers will appear and be used.
As we know thanks to properties of qubits (namely their superposition, when a qubit can take values 0 and 1 simultaneously) they can break many popular cryptographic algorithms at the moment (RSA and ECDSA for example).

So what to do about it?

That's why the post-quantum cryptography was invented. 

I'll talk briefly about its algorithms and how it works, more details can be found in the archive below. 

Now the development of post-quantum algorithms is mainly engaged in NIST .

The NIST competition for the selection of quantum-resistant cryptoalgorithms is a set of activities to standardize a set of post-quantum schemes The competition was launched in 2017, its third round is now completed.

The development of such algorithms is important now.
This is due to two factors. First, there has been notable progress in the development of quantum computers, including theoretical methods for quantum error correction and fault-tolerant quantum computing, as well as experimental demonstrations of physical qubits and entanglement operations in architectures that can potentially scale to larger systems.🧩

Post quantum algorithms, include:

Elliptic curves: Elliptic curve-based cryptography requires an attacker to solve a discrete logarithm problem on an elliptic curve E over a finite field F p with p elements, where p is a prime number. Concretely, his problem is to find a secret integer n , for which P' = nP , after entering two points P and P' on E , where multiplication by n is done by a repeated construction of a tangent and a chord which addresses the points from E in a wrong and unpredictable way. But the problem with discrete logarithm is unraveling this iteration.

Lattices: A lattice is an infinite grid of points, often arranged in two-dimensional space . The most important computational problem based on the lattice is the Shortest Vector Problem, which asks us to approximate the minimal Euclidean length of a non-zero vector to the lattice

Isogenies: it is a rational mapping between two elliptic curves which is a homomorphism. If there exists this kind of mapping between two curves, they are called isogenies. When we consider them, it turns out that the graph of their l-isogenies has a number of properties that allow to build cryptographic schemes, the robustness of which is based on the assumption of the complexity of the problem of finding a path between two vertices in this graph.

Hash functions: a hash function can be defined as a compression function with a number of properties determined by the application area of hashing.

Hybrids: combining different algorithms together .
#cryptography #quantum_computer #quantum_mechanics #post_quantum #protection