Issue link: https://read.uberflip.com/i/1428383
LoRaWAN 1.0.3 Specification ©2018 LoRa™ Alliance Page 42 of 72 The authors reserve the right to change specifications without notice. PingSlotInfoReq to the Network Server. Once this command is acknowledged the 1161 device MAY restart class B operation with the new ping-slot periodicity 1162 • If no beacon has been received for a given period (as defined in Section 12.2), the 1163 synchronization with the network is lost. The MAC layer should inform the application 1164 layer that it has switched back to Class A. As a consequence the end-device 1165 LoRaWAN layer stops setting the Class B bit in all uplinks and this informs the Network 1166 Server that the end-device is no longer in Class B mode. The end-device application 1167 can try to switch back to Class B periodically. This will restart this process starting with 1168 a beacon search. 1169 The following diagram illustrates the concept of beacon reception slots and ping slots. 1170 1171 Figure 11: Beacon reception slot and ping slots 1172 In this example, given the beacon period is 128 s, the end-device also opens a ping reception 1173 slot every 32 s. Most of the time this ping slot is not used by the server and therefore the end- 1174 device reception window is closed as soon as the radio transceiver has assessed that no 1175 preamble is present on the radio channel. If a preamble is detected the radio transceiver will 1176 stay on until the downlink frame is demodulated. The MAC layer will then process the frame, 1177 check that its address field matches the end-device address and that the Message Integrity 1178 Check is valid before forwarding it to the application layer. 1179 gateway End-device End-device RX windows Network beacon transmission Network beacon transmission ping End-device response