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ERRATA Allow Downlink TransmissionsThe LoRa Alliance © 2021 2 1. Discussion The description of downlink is overly restrictive, but not normative. Clarify to remove the restriction which imply that D2D is prohibited (same text as 1.2.0). Relax other restriction. 2. Proposed changes (normative/informative) ************************ Start of proposed change for 3.2 ************************* 3.2 Downlink Messages Downlink packets are sent to one or more end-devices, typically transmitted by a Network Server through one or more gateways. Each downlink message is sent by the Network Server to only one end-device and is relayed by a single gateway. 1 Downlink messages use the radio packet explicit mode in which the LoRa physical header (PHDR) and a header CRC (PHDR_CRC) are included. 2 Downlink PHY: Preamble PHDR PHDR_CRC PHYPayload Figure 13: Downlink PHY structure ************************* End of proposed change for 3.2 **************************** ************************ Start of proposed change for 4.3.1.5************************* 4.1.3.5 Frame counter (FCnt) Each end-device has three frame counters to keep track of the number of data frames sent uplink to the Network Server (FCntUp), and sent downlink from the Network Server to the device (FCntDown). In the downlink direction two different frame counter scheme exists; a single counter scheme in which all ports share the same downlink frame counter FCntDown when the device operates as a LoRaWAN1.0 device, and a two-counter scheme in which a separate NFCntDown is used for MAC communication on port 0 and when the FPort field is missing, and another AFCntDown is used for all other ports when the device operates as a LoRaWAN1.1 device. In the two counters scheme the NFCntDown is managed by the Network Server, whereas the AFCntDown is managed by the application server. Note: LoRaWAN v1.0 and earlier support only one FCntDown counter (shared across all ports) and the Network Server must take care to support this scheme for devices prior to LoRaWAN v1.1. ************************* End of proposed change for 4.3.1.5 **************************** 1 This specification does not describe the transmission of multicast messages from a network server to many end-devices. 2 No payload integrity check is done at this level to keep messages as short as possible with minimum impact on any duty-cycle limitations of the ISM bands used. Commented [DK1]: Remove footnote, it is incorrect (says we don't describe multicast, but we do)

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