A method, a device, and a program product for backing up data in the Internet of Things (IoT) is disclosed. An IoT system includes an IoT manager and a plurality of IoT devices. In response to receiving a registration request for registering an IoT device among a plurality of IoT devices with an IoT manager, a signature public key is received from the IoT device. Atomic data associated with the IoT device is received that includes a signature generated by using a signature private key corresponding to the signature public key. The signature is verified based on the signature public key. In response to the signature being successfully verified, a backup data package for backup is generated based on the atomic data. Accordingly, data may be backed up in the IoT with higher performance, thereby improving the security and reliability of the entire IoT.