Issue link: https://read.uberflip.com/i/1428350
LoRaWAN Remote Multicast Setup v1.0.0 Specification ©2018 LoRa Alliance™ Page 13 of 18 The authors reserve the right to change specifications without notice. The end-device acknowledges the reception of this message by sending a 375 McClassCSessionAns message on the same port with the following payload: 376 377 Field Status&McGroupID (cond)TimeToStart Size (bytes) 1 3 Table 18: McClassCSessionAns 378 Where: 379 380 Status&McGroupID Fields RFU McGroupUndefined FreqError DRError McGroupID Size (bits) 3bits 1bit 1bit 1bit 2bits Table 19: McClassCSessionAns Status&McGroupID field 381 382 FreqError bit is set to 1 if the DLFrequ frequency set by the network is not usable for the 383 end-device. 384 385 DRError bit is set to 1 if the classC downlink Data Rate set by the network is not defined. 386 387 McGroupUndefined is set 1 if the McGroupID specified by the command is not defined in the 388 end-device (was not created before calling this command). 389 390 If no errors are present, the TimeToStart field encodes the number of seconds from the 391 McClassCSessionAns uplink to the beginning of the multicast session. This allows the 392 server to check that the end-device clock is well synchronized and that the end-device will 393 effectively switch to classC exactly at the right moment (with second accuracy). This is 394 possible because all uplinks are accurately time stamped by the network gateways (at least 395 with an accuracy better than the second). 396 4.6 McClassBSessionReq & Ans 397 398 This message is only used to setup a temporary ClassB multicast session associated with a 399 multicast context. 400 The payload of the message is: 401 402 Table 20: McClassBSessionReq 403 Where: 404 McGroupIDHeader Fields RFU McGroupID Size (bits) 6bits 2bits Table 21: McClassBSessionReq McGroupIDHeader field 405 And where: 406 407 TimeOutPeriodicity Fields RFU Periodicity TimeOut Size (bits) 1bits 3bits 4bits Table 22: McClassBSessionReq TimeOutPeriodicity field 408 Field McGroupIDHeader Session Time TimeOutPeriodicity DLFrequ DR Size (bytes) 1 4 1 3 1