What are the principles of a dynamic password?

A dynamic password is a temporary password that is calculated based on an algorithm that does not need a network. The app requests a door lock's dynamic password from the Tuya server over a third-party API. When the door lock receives a suspicious dynamic password, it sends the password to the Tuya Wi-Fi or Zigbee module with the current time and administrator password. The module then calculates the password based on the saved initial private key and compares the calculated password with the password that you enter. If they are the same, the module tells the MCU to open the door. If they are different, the module tells the MCU not to open the door.