https://access.redhat.com/blogs/766093/posts/3031361?sc_cid=7016000000127ECAAY

The SSL/TLS protocol uses RSA, Diffie-Hellman (DH) or Elliptic Curve Diffie-Hellman (ECDH) primitives for the key exchange algorithm.

RSA is based on the fact that when given a product of two large prime numbers, factorizing the product (which is the public key) is computationally intensive, but a quantum computer could efficiently solve this problem using Shor’s algorithm. Similarly, DH and ECDH key exchanges could all be broken very easily using sufficiently large quantum computers.

For symmetric ciphers, the story is slightly different. It has been proven that applying Grover’s algorithm the strength of symmetric key lengths are effectively halved: AES-256 would have the same security against an attack using Grover’s algorithm that AES-128 has against classical brute-force search. Hashes are also affected in the same way symmetric algorithms are.

Therefore, we need new algorithms which are more resistant to quantum computations. This article introduces you to 5 proposals, which are under study.

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## Tomi Engdahl says:

World’s Leading Physicist Says Quantum Computers Are “Tools of Destruction, Not Creation”

by Patrick Caughill on August 9, 2017

https://futurism.com/worlds-leading-physicist-says-quantum-computers-are-tools-of-destruction-not-creation/

Weapon of Mass Disruption

Quantum Computers are heralded as the next step in the evolution of data processing. The future of this technology promises us a tool that can outperform any conventional system, handling more data and at faster speeds than even the most powerful of today’s supercomputers.

However, at the present juncture, much of the science dedicated to this field is still focused on the technology’s ultimate utilization. We know that quantum computers could manage data at a rate that is remarkable, but exactly what kind of data processing will they be good for?

This uncertainty raises some interesting questions about the potential impact of such a theoretically powerful tool.

“No encryption existing today would be able to hide from the processing power of a functioning quantum computer.”

Last month, some of the leading names in quantum technologies gathered at the semi-annual International Conference on Quantum Technologies in Moscow. Futurism was in attendance and was able to sit and talk with some of these scientists about how their work is moving us closer to practical quantum computers, and what impact such developments will have on society.

What is it about quantum computers that would incite such a claim? In the end, it comes down to one thing, which happens to be one of the most talked about potential applications for the technology: Breaking modern cryptography.

With Great Power…

Today, all sensitive digital information sent over the internet is encrypted in order to protect the privacy of the parties involved. Already, we have seen instances where hackers were able to seize this information by breaking the encryption. According to Lvovsky, the advent of the quantum computer will only make that process easier and faster.

In fact, he asserts that no encryption existing today would be able to hide from the processing power of a functioning quantum computer. Medical records, financial information, even the secrets of governments and military organizations would be free for the taking—meaning that the entire world order could be threatened by this technology.

The consensus between other experts is, essentially, that Lvovsky isn’t wrong. “In a sense, he’s right,” Wenjamin Rosenfeld, a physics professor at the Ludwig Maximilian University of Munich, stated in an interview. He continued, “taking a quantum computer as a computer, there’s basically not much you can do with this at the moment;” however, he went on to explain that this may soon be changing.

To break this down, there are only two quantum algorithms at the moment, one to allow a quantum computer to search a database, and the other, Shor’s algorithm, which can be used by a quantum computer to break encryption.

Quantum computers may not be capable of the physical destruction of a nuclear bomb, but their potential application is the digital equivalent.