Symmetric/Asymmetric Encryption and Digital Signatures

As we have already explained, symmetric cryptography is mainly based on randomization. On the other hand, asymmetric cryptography does not rely only on randomization because it allows an easy computation in the forward direction (e.g., generating the key pair), but makes the inverse computation extremely hard (e.g. discovering the private key from the public key). The main building block for asymmetric cryptography is so-called intractable problems.

Intractable problems

Intractable problems are problems for which there is no known efficient algorithm to solve.

Types

There are two main types of intractable problems:

The discrete logarithm problem

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