The three new specifications include the LoRaWAN Application Layer Clock Synchronization Specification v1.0.0; LoRaWAN Remote Multicast Setup Specification v1.0.0; and LoRaWAN Fragmented Data Block Transport Specification v1.0.0. Together, the new specifications enable FUOTA, says the organization, however, three separate specifications have been issued because each can be used independently.
For example, remote multicast setup protocol can be used standalone to send messages to a group of end devices, while fragmentation can be used on its own to send a large file to a single end-device (unicast). And time synchronization also can be used as a standalone capability.
Security – a strong focus of this development effort – is addressed in the Multicast and Fragmentation specifications. For multicast, the protocol has a means to securely deliver a cryptographic key to the group of end devices, while in fragmentation, a section is dedicated to file integrity and authentication recommendations.