10.1 Passwords and Authentication

Notes

Authentication proves who you are. Passwords are the most common method, but weak ones are easy to guess.

• Strong passwords are long (12 or more characters), unique for each account, and not based on personal facts.
• Attackers use brute force (trying every combination) and dictionary attacks (trying common words and passwords like password123).
• Each extra character multiplies the number of possible passwords. A 4-digit PIN has 10 x 10 x 10 x 10 = 10,000 possibilities.
• Two-factor authentication (2FA) adds a second proof, such as a code sent to your phone, so a stolen password alone is not enough.
• A password manager can create and store unique passwords.