The quantum computing race is on and some of the big technology companies like IBM, Microsoft, Intel, or Google are already working on revolutionizing what we know as classic computing.
Google and IBM have even announced that they developed the first quantum computers.
To begin to understand a little bit about this race and what cryptography has to do with it, let’s first see what quantum computing is all about.
Quantum computing is the discipline of study whose object is to develop computer technology from the principles of quantum theory. According to the laws of quantum physics, the tremendous processing capacity of quantum computers is derived from their ability to be in multiple states and perform tasks using all possible permutations simultaneously 1.
These computers are not like traditional computers, they work with photons of light and ‘cubits’; unlike traditional computers that use a binary system, quantum moves away from this system.
The ‘cubits‘, unlike the ‘bits‘, can take several values at once and can develop calculations that a conventional computer cannot do, as we can see it is not as simple as changing parts of our traditional computer to make it quantum, because the principle with which both works is totally different.
Now, with such powerful technology in development, with big companies like Google and IBM advertising their advances in the first computers of this kind, the cryptographic world has not been left behind.
Quantum cryptography differs from traditional encryption systems in that its security model incorporates physical, not just mathematical, principles.
Essentially, quantum cryptography uses individual particles/light waves (photons) and their intrinsic quantum properties to develop an impregnable system (because it is impossible to measure the quantum state of any system without altering that system).
Now, the main technology that uses cryptographic algorithms is Blockchain, and many sectors have joined this technology to protect their information and that of their users.
The Blockchain networks, including the Bitcoin architecture, are based on two algorithms: The Elliptic Curve Digital Signature Algorithm (ECDSA) for digital signatures and SHA-256 as a hash function.
Here the public and private keys would be encrypted by a series of photons that are transferred between the two parties that want to share secret information.
Although there is a lot of talk about replacing traditional computers with quantum computers and block mining using this technology, there is still a lot of work to be done and several challenges to overcome. One of the main problems of these computers is to be able to operate outside a laboratory and for quantum cryptography to be able to identify new cryptographic algorithms that are resistant to attacks by quantum computers.