Issue link: https://read.uberflip.com/i/1428383
LoRaWAN 1.0.3 Specification
©2018 LoRa™ Alliance Page 38 of 72
The authors reserve the right to change
specifications without notice.
7 Retransmissions back-off 1065
1066
Uplink frames that: 1067
• Require an acknowledgement or an anwser by the network or an application 1068
server, and are retransmitted by the device if the acknowledgement or answer is not 1069
received. 1070
and 1071
• can be triggered by an external event causing synchronization across a large 1072
(>100) number of devices (power outage, radio jamming, network outage, 1073
earthquake…) 1074
can trigger a catastrophic, self-persisting, radio network overload situation. 1075
1076
Note: An example of such uplink frame is typically the JoinRequest if the 1077
implementation of a group of end-devices decides to reset the MAC 1078
layer in the case of a network outage. 1079
The whole group of end-device will start broadcasting JoinRequest 1080
uplinks and will only stops when receiving a JoinResponse from the 1081
network. 1082
1083
1084
For those frame retransmissions, the interval between the end of the RX2 slot and the next 1085
uplink retransmission SHALL be random and follow a different sequence for every device (For 1086
example using a pseudo-random generator seeded with the device's address) .The 1087
transmission duty-cycle of such message SHALL respect the local regulation and the following 1088
limits, whichever is more constraining: 1089
1090
Aggregated during the first
hour following power-up or
reset
T0