Key Stretching Algorithms
Key stretching is where you append a random set of characters to a password to increase the size of the password and its hash, ensuring that a brute-force attack needs more compute time to crack the password.
- BCRYPT: BCRYPT is a password-hashing algorithm based on the Blowfish cipher. It is used to salt the passwords. A random string is appended to the password to increase the password length to help increase the compute time for a brute-force attack.
- PBKDF2: PBKDF2 stores passwords with a random salt and with the password hash using HMAC. It then iterates, which forces the regeneration of every password and prevents any rainbow table attack.
Tip
Symmetric encryption is used to encrypt large amounts of data as they have small, fast keys and use block ciphers.
