Hybrid Encryption
Sometimes mixing two things together makes good sense. Do you remember the commercial, “You got your chocolate in my peanut butter?” While you may not consider cryptography as tasty as chocolate, there is a real benefit to combining both symmetric and asymmetric encryption. Symmetric encryption is fast, but key distribution is a problem. Asymmetric encryption offers easy key distribution, but it’s not suited for large amounts of data. Combining the two into hybrid encryption uses the advantages of each and results in a truly powerful system. Public key cryptography is used as a key encapsulation scheme, and the private key cryptography is used as a data encapsulation scheme. Here is how the system works. If Bob wants to send a message to Alice, the following occurs:
- Bob generates a random private key for a data encapsulation scheme. This session key is a symmetric key.
- The data encapsulation happens when Bob encrypts the message using the symmetric...