When developing IoT devices, one of the most difficult problems to solve is how to update the firmware on the device. Once the device is deployed, firmware updates play a critical part in its lifetime, particularly when devices have a long lifetime, are deployed in remote or inaccessible areas or where manual intervention is cost prohibitive or otherwise difficult.

In order for a device to apply an update, it has to make several decisions about the update such as does it trust the author of the update, has the firmware been corrupted, does the firmware update apply to this device, is the update older than the active firmware, when should the device apply the update, how should the device apply the update, what kind of firmware binary is it, where should the update be obtained and where should the firmware be stored?