Fields in up messages from MQTT

[kirill.chugunov01@mail.ru]

Hello,

I would like to a bit description for up messages from MQTT.
I’ve read the article MQTT Messages. There have descriptions of messages from MQTT. But I didn’t found few fields. Can I have desriptions for these? I am about fields:

• nonce (I found in join_request & packet_recv topics)
• ipol (I found in the packet_sent topic)
• ncrc (I found in the packet_sent topic)
• powe (I found in the packet_sent topic)
• twnd (I found in the packet_sent topic)

Also, I would like to get more deeply description for these fields:

• rfch (I don’t understand what this)
• fcnt & seqn (Why Multitech send packet sequence number of different bit size? )
• cls (What does show this control byte?)

Thanks and Regards
Kirill

[Jason Reiss]

Fields not listed below are packet forwarder protocol
https://github.com/Lora-net/sx1302_hal/blob/master/packet_forwarder/PROTOCOL.md

Nonce is devnonce in a join request
Twnd is the rx window the device is receiving the packet. RX1 1, RX2 2, RXC 3, RXB 4

Fcnt is the 16 bit FCnt in the lorawan frame semt over the air
Seqn is the 32 bit full counter used for MIC and decryption
Cls is a bit in FCtrl byte that signifies Class A if 0 or Class B device if 1

[Jason Reiss]

You can read more about fcnt and fctrl in the spec.
https://resources.lora-alliance.org/technical-specifications/ts001-1-0-4-lorawan-l2-1-0-4-specification

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