Dynamic password, also known as one-time password, means that the user's password changes dynamically according to time or usage times, and each password is used only once. Dynamic password uses a special kind of hardware called dynamic token, which is the size of a flash drive, similar to a electronic watch. It has a built-in power supply, a password generation chip and a display screen. The password generation chip runs a special password algorithm, generates the current password according to the current time or usage times, and displays it on the display screen. The authentication server uses the same algorithm to calculate the current valid password. Because the password used every time must be generated by a dynamic token, only legitimate users hold it.

Dynamic token, two-factor authentication [1]

Hardware, so as long as the password is verified, the system can think that the user's identity is reliable. Users use different passwords every time. Even if a hacker intercepts the password once, he can't use it to impersonate a legitimate user.