Issue link: https://read.uberflip.com/i/1428356
LoRaWAN Fragmented Data Block Transport v1.0.0 Specification ©2018 LoRa Alliance™ Page 6 of 30 The authors reserve the right to change specifications without notice. 2 Introduction 121 122 This document proposes an application layer messaging package running over LoRaWAN to 123 perform the following operations on a fleet of end-devices: 124 • Send a fragmented block of data to one or many end-devices 125 126 All messages described in this document are transported as application layer messages. As 127 such, all unicast messages (uplink or downlink) are encrypted by the LoRaWAN MAC layer 128 using the end-device's AppSKey. Downlink multicast messages are encrypted using a 129 multicast group McAppSKey common to all end-devices of the group. The setup of the group 130 is described in [RPD_Remote_Multicast_Setup]. 131 The data block transported may be a firmware upgrade, but this document is not specific to 132 firmware upgrade. Any large (from 1kBytes to X Kbytes) data file may be sent to a (group of) 133 end-device using this protocol. 134 135 The "fragmentation control" package can be used to: 136 • Setup / report / delete fragmentation transport sessions 137 • Several fragmentation sessions MAY be supported simultaneously by an end-device 138 • Fragmentation can be used either over multicast or unicast 139 • Authenticate a data block once reconstructed (TBD) 140 • Report on the status of a fragmentation session 141 142 This package uses a dedicated port to separate its traffic from the rest of the applicative 143 traffic. 144