PIN limitations in Sierra: PIN_ALPHA_NUM should accept special characters
PINALPHANUM does not accept special characters.
If Vega Discover continues to be limited by wwwoptions for PIN creation, this option should accept special characters.
PIN Best Practice: The strongest defense combines a long length (12+ characters) with a true random mix of letters, numbers, and symbols.
Length vs. Complexity: Recent security guidelines emphasize that making a password longer (like using a multi-word passphrase) is often more effective than adding a single symbol to a short word. That said, library users do use special characters and want them included in their library PIN.
Adding symbols increases the character set size from 62 alphanumeric options to 94+ total keyboard symbols, making combinations harder to guess.
Exponential Combinations: Each added symbol type significantly increases the total number of permutations a computer must guess in a brute-force attack