40 Algorithms Every Programmer Should Know

Asymmetric Encryption

In the 1970s, asymmetric encryption was devised to address some of the weaknesses of symmetric encryption that we discussed in the previous section.

The first step in asymmetric encryption is to generate two different keys that look totally different but are algorithmically related. One of them is chosen as the private key, K_pr, and the other one is chosen as the public key, K_pu. Mathematically, we can represent this as follows:

E_Kpr(P) = C

Here, P is the plain text and C is the cipher text.

We can decrypt it as follows:

D_Kpu(C) = P

Public keys are supposed to be freely distributed and private keys are kept secret by the owner of the key pair.

The fundamental principle is that if you encrypt with one of the keys, the ...