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