STEP 1:

Select two prime numbers p and q

STEP 2:

n = p x q

STEP 3:

Totient(n) = (p-1) x (q-1)

STEP 4:

Enter another prime number(e) between 3 and φ(n). This number must be relatively prime to φ(n) also. We look for a number between 3 and φ(n) because 3 is the first prime number that can be used.

We will use Modular inverse function d = modinv(e,φ(n));

STEP 5 - Encryption:

encrypt(x) = x^e mod n

STEP 6 - Decryption:

decrypt(x) = x^d mod n