Q. Illustrate about RSA Encryption?

RSA Encryption

- Public key encryption technique

- Encryption steps:

- Encode data to be encrypted as a number to create the plaintext P

- Calculate the ciphertext C as C = PKp modulo N

(Divide PKp by N also keep only the remainder)

- Send C as the ciphertext

- Decryption steps:

- Receive C the ciphertext

- Calculate plaintext P = CKs modulo N

- Decode P to the original data

- Choosing Kp, Ks, and N

- Choose 2 prime numbers p and q (large # of digits - 200 or more)

- Calculate N = p * q

- Select Kp so that it is not a factor of (p -1)*(q -1)

- Select Ks so that (Kp * Ks) modulo (p - 1)*(q -1) = 1