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# How does public-key cryptography work?

The two keys used in public-key cryptography are related by a mathematical function

* These functions are "easy" to perform but "hard" to reverse

Commonly used functioons include:

* Factoring
* Discrete logarithm
* Elliptic-curve descrete logarithm

Public-key cryptography is secure as long as these problems remain "hard"

* Quantum computing threatens this