For whole disk encryption (WDE) or any sort of password protected service where you cannot execute software (primary authentication), I encourage the use of pass phrases. Dice ware is nice. Something such as this:
"lua ham purple day girl"
The challenge with primary authentication passwords is that users typically cannot use a password manager or generator to recall the password and thus must be able to recall something that they can easily type and end-up selecting weak passwords. There are some exceptions to this (yubikey, etc) but most normal users don't or cannot use them for various reasons, so go with a nice pass phrase like the one above.
Forego the cultural references here. (Should be obvious, but you have to assume the attacker is familiar with you in specific and can guess what you'll know.)
If we know the "algorithm" for your password choice (all lowercase, english words, space delimited, at least two words) that greatly reduces the time needed to guess the password. I wonder how much time that would take to crack on modern hardware...
> I wonder how much time that would take to crack on modern hardware...
A very long time. You're still looking at a total of 3-5 words you need to guess (9-25 characters based on 3-5 letters per word), in the right combination, and assuming all words are English or popular colloquialisms...
("greatly reducing" is still not going to make brute forcing a realistic choice).
It would still take a very long time but remember we're not iterating by character anymore. Each word is a 'character' and our alphabet is the english dictionary.
So for the example above, we have to guess 5 slots in the passphrase and each slot has [number of words in english dict] possibilities. And also we'd probably start guessing assuming 2 word passphrases and have to exhaust all of 2, 3 and 4 before we start guessing 5 word combinations.
"lua ham purple day girl"
The challenge with primary authentication passwords is that users typically cannot use a password manager or generator to recall the password and thus must be able to recall something that they can easily type and end-up selecting weak passwords. There are some exceptions to this (yubikey, etc) but most normal users don't or cannot use them for various reasons, so go with a nice pass phrase like the one above.