The network of smart lock is a typical three-layer structure of IoT. They are perception layer, transmission layer and application layer. Perception layer consists of intelligent lock and smart phone APP, transmission layer includes smart gateway and mobile communication base station, and application layer is the intelligent lock cloud platform.
In the perception layer, most of smart locks are powered by batteries. Due to the limitation of power consumption, its communication modes mainly include Bluetooth, ZigBee, NB-IoT, 433MHz and 315MHz. Some locks are powered by alternating current, they usually communicate with the cloud through WIFI.
In the transport layer, the communication modes are mainly household broadband (WIFI/ Ethernet) and mobile communication (3G/4G).
In the application layer, namely the cloud service of intelligent lock, it is mainly responsible for the device access, identity authentication, logic control, data analysis and business display of intelligent lock. At present, intelligent door lock cloud services are mainly deployed in the cloud, such as Ali Cloud, AWS, Azure and Tencent Cloud, as well as the private cloud of each manufacturer.
In temporary password unlock mode, the user will obtain the temporary password from the cloud through mobile phone APP, and send the temporary password to the visitor through SMS, WeChat or mobile phone APP. When visitor inputs the received temporary password on the lock, the lock will compare the password with the current temporary password automatically which it is generated by the cloud. If successful, the lock will be unlocked.
At present, the commonly used and reliable biometrical keys are mainly fingerprint, palm print, iris and face. Locks store biometric features, such as fingerprints, palm prints, iris and faces, to cloud. When you unlock, the lock will compare the user's biometrical keys with those stored in the cloud. If the comparison is successful, the lock will be opened.
Smart cards for smart locks are mainly RFID cards, NFC cards and CPU cards. These locks are mainly used in hotel and apartment.
About RFID card lock, the access control system will write a string representing the identity of the card to the RFID card. When you unlock, the lock will extract the string in the RFID card and transfer it to the cloud for comparison. If the comparison is successful, the lock will be unlocked.
About NFC card and CPU card, the access control system will write the private key and public key representing the identity of the card to these 2 cards. When you unlock, the lock and the cloud will conduct dual identity authentication for the card. If the authentication is successful, the lock will be unlocked.
In APP unlock mode, the cloud will bind the door lock to the APP on the specified phone.
When you completes the identity authentication on the mobile phone, and then clicks the unlock button on APP. The intelligent lock will receive the unlock command from the cloud, and then the lock will be unlocked.