Pass Phrases

Pass phrases[4] are essentially what is used as the root of a mnemonic password. They are easier to remember and much longer which results in a password being much more resilient to attack by brute force. Pass phrases tend to be much more complex due to the use of upper and lower case characters, white-space characters, as well as special characters like punctuation and numbers.

However, pass phrases have their own sets of problems. Many authentication systems do not support lengthy authentication tokens, thus resulting in pass phrases that are not consistently usable. Like the aforementioned methods, the same pass phrase may be reused across multiple authentication systems.