Issue link: https://read.uberflip.com/i/1464683
LoRaWAN ® Fragmented Data Block Transport Specification TS004-2.0.0 ©2022 LoRa Alliance ® Page 11 of 32 The authors reserve the right to change specifications without notice. 260 Size (octets) 1 2 1 FragParam Payload Status Received&index MissingFrag Table 6: FragSessionStatusAns The format of the Status field is: 261 262 Bits 7:3 2 1 0 Status field RFU Session does not exist MICError MemoryError Table 7: FragSessionStatusAns Status format The end-device SHALL set bit 2 of the Status field to the value of 1 if the requested 263 fragmentation session does not exist and SHALL NOT include the Received&index and 264 MissingFrag fields. 265 266 If MissingFrag is equal to 0, the MICError bit in the Status field signals the result of 267 the MIC check on the reassembled data block. A value of 0 means that the MIC check is 268 successful. A value of 1 means that the MIC computed by the end-device and the one 269 provided in the corresponding FragSessionSetupReq command do not match. The data 270 block will not be processed by the end-device. If MissingFrag is different from 0, the 271 MICError bit SHALL be 0. 272 273 When set to 1, the bit MemoryError signals that the defragmentation process was aborted 274 because the allocated memory for defragmentation was exceeded. 275 276 The Received&index field is used by the fragmentation receiver to report its 277 defragmentation status for the fragmentation session FragIndex and is defined as follows: 278 279 Bits 15:14 13:0 Received&index Field FragIndex NbFragReceived Table 8: FragSessionStatusAns Received&index format NbFragReceived is the total number of fragments received, including coded, uncoded, 280 and repeated, for this fragmentation session, since the session was created. 281 282 MissingFrag is the number of uncoded fragments still missing (not received or not 283 reconstructed). It corresponds to the minimum number of independent coded fragments still 284 required before being able to reconstruct the data block. In the case where the block was 285 already successfully reassembled, this field SHOULD be 0. If more than 255 fragments are 286 missing, MissingFrag SHALL be set to 255. 287 288