When using RSA for encryption and decryption of general data, it reverses the key set usage. Unlike signature verification, it uses the receiver’s public key to encrypt the data, and it uses the receiver’s private key in decrypting the data. Thus, there is no need to exchange any keys in this scenario.
There are two broad components when it comes to RSA cryptography, they are:
- Key Generation: Generating the keys to be used for encrypting and decrypting the data to be exchanged.
- Encryption/Decryption Function: The steps that need to be run when scrambling and recovering the data.
You need to generate public and private keys before running the functions to generate your ciphertext and plaintext. They use certain variables and parameters, all of which are explained below:
- Choose two large prime numbers (p and q)
- Calculate n = p*q and z = (p-1)(q-1)
- Choose a number e where 1 < e < z
- Calculate d = e-1mod(p-1)(q-1)
- You can bundle private key pair as (n,d)
- You can bundle public key pair as (n,e)
- No Key Sharing: RSA encryption depends on using the receiver’s public key, so you don’t have to share any secret key to receive messages from others.
- Proof of Authenticity: Since the key pairs are related to each other, a receiver can’t intercept the message since they won’t have the correct private key to decrypt the information.
- Faster Encryption: The encryption process is faster than that of the DSA algorithm.
- Data Can’t Be Modified: Data will be tamper-proof in transit since meddling with the data will alter the usage of the keys. And the private key won’t be able to decrypt the information, hence alerting the receiver of manipulation.
