Password please
Good Keys, bad keys When using encryption, good encryption keys are essential. They must be generated randomly and must contain enough entropy. Otherwise we’ll open wide range of attacks on encrypted data. In addition to the key, we also need Initialization Vector (IV) which doesn’t necessarily have to be secret, but still it should be either pseudorandom or (in case of some encryption primitives) just unique when used together with the same key (IV is then also called a nonce).