Studying CISSP, you may come across Public Key Infrastructure (PKI) RSA algorithm and be curious how it works.
In short, RSA algorithm is used to produce a key pair in order to implement asymmetric encryption/decryption operation. The key pair, one private and one public are generated. Then one can encrypt the message and the other can decrypt the message and vice versa.
For the above to be reliable, it should be extremely costly, time consuming and difficult to extract a private key from its public key pair, and vice versa. But it should be so simple to use a private key to decrypt a message encrypted with the public key, and vice versa.
RSA is an algorithm to find such key pairs, using mathematical calculations.
