Password-based cryptography

Password-based cryptography is the study of password-based key encryption, decryption, and authorization. It generally refers two distinct classes of methods:

• Single-party methods
• Multi-party methods

Single party methods

Some systems attempt to derive a cryptographic key directly from a password. However, such practice is generally ill-advised when there is a threat of brute-force attack. Techniques to mitigate such attack include passphrases and iterated (deliberately slow) password-based key derivation functions such as PBKDF2 (RFC 2898).

Multi-party methods

Password-authenticated key agreement systems allow two or more parties that agree on a password (or password-related data) to derive shared keys without exposing the password or keys to network attack.^[1] Earlier generations of challenge–response authentication systems have also been used with passwords, but these have generally been subject to eavesdropping and/or brute-force attacks on the password.

See also

• Password
• Passphrase
• Password-authenticated key agreement