This key is known as a session key . Public-key encryption uses two different keys, a public key and a private key. The public key is widely distributed while the private key is secret. Aside from key length and encryption approach, other factors and variables impact the success of a cryptographic system. For example, different cipher modes, in coordination with initialization vectors and salt values , can be used to modify the encryption method.
Cipher modes define the method in which data is encrypted.
The stream cipher mode encodes data one bit at a time. The block cipher mode encodes data one block at a time. Although it tends to execute more slowly than stream cipher, block cipher is more secure. For more information on these modes, see Encrypting and Decrypting Data . Initialization vectors are random numbers used as starting points when encoding data.