Issue link: https://read.uberflip.com/i/1464683
LoRaWAN ® Fragmented Data Block Transport Specification TS004-2.0.0 ©2022 LoRa Alliance ® Page 8 of 32 The authors reserve the right to change specifications without notice. 3 Fragmented Data Block Transport Package 196 197 The PackageIdentifier of the fragmentation transport package is 3. The 198 PackageVersion of this package is version 2. This version of the package is not 199 compatible with the earlier version of the same package. 200 201 This package supports all the commands necessary to reliably transport a large data block 202 from a fragmentation server to an end-device (using unicast) or a group of end-devices (if 203 multicast is used over Class B or Class C). This package requires a dedicated port. It is 204 RECOMMENDED that a default port value of 201 be used to promote interoperability, 205 though implementations MAY use a value from those not assigned by the LoRa Alliance. 206 Once declared, this port SHALL NOT be used for any other purposes. 207 208 All fragmentation-related messages are exchanged on this port using an application payload 209 and encrypted using the end-device's AppSKey or the McAppSKey. 210 211 All unicast or multicast control messages use the same format: 212 213 Command1 Command1 Payload Command2 Command2 payload …. Table 1: Format of control messages A message MAY carry more than one command, except for the DataFragment command, 214 which SHALL be the only command in a message's payload. The length of each command's 215 payload is fixed or can be determined unambiguously as a function of the command. 216 Commands are executed from first to last. Each command SHALL be individually 217 acknowledged by the end-device on the same FPort. 218 219