Issue link: https://read.uberflip.com/i/1428395
LoRaWAN ® L2 1.0.4 Specification © 2020 LoRa Alliance ® Page 24 of 90 The authors reserve the right to change specifications without notice. Note: If the test runs on an end-device connected to a live network, the 750 way the test application on the Network side learns the AppSKey is 751 beyond the scope of the LoRaWAN specification. If the test runs using 752 OTAA on a dedicated test bench (not a live network), the way the 753 AppKey is communicated to the test bench for a secured Join process 754 is also beyond the scope of this specification. 755 756 The test protocol running at the application layer is defined in [TS009]. 757 758 759 Size (octets) 7..22 0..1 0..N MACPayload FHDR FPort FRMPayload Table 10: MACPayload format 760 761 762 N is the number of octets of the application payload and SHALL be equal to or less than 763 N ≤ M − 1 − (length of FHDR in octets), where M is the maximum MACPayload length. 764 The valid ranges of both N and M are region-specific and defined in the "LoRaWAN Regional 765 Parameters" [RP002] document. 766 4.3.3 MAC frame payload encryption (FRMPayload) 767 If a data frame carries a payload (FRMPayload), it SHALL be encrypted before the message 768 integrity code (MIC) is calculated. 769 The encryption scheme is based on the generic algorithm described in IEEE 802.15.4/2006 770 Annex B [IEEE802154] using AES encryption with a key length of 128 bits. AES encryption is 771 defined in [NIST-AES]. 772 Key K depends on the FPort of the data frame: 773 774 FPort K 0 NwkSKey 1..255 AppSKey Table 11: FPort list 775 776 777 The encrypted fields are pld = FRMPayload. 778 For each data frame, the algorithm defines a sequence of Blocks A i for i = 1..k, where k = 779 ceil(len(pld) / 16): 780 781 Size (octets) 1 4 1 4 4 1 1 A i 0x01 4 × 0x00 Dir DevAddr FCntUp or FCntDown 0x00 i Table 12: A i format 782 783 784