Increment devNonce on every join request

[cjhdev]

Increment devNonce on every join request

[cjhdev]

I must confess I haven't seen this problem but then I don't have much experience with devices in the field.

It doesn't make sense to me that the server would mark a join request as already seen if it hasn't received confirmation that the device that it received the join accept. The confirmation being a data frame encrypted with the new session keys.

I looked up that line in the L2 spec. They talk about "Join Request" as well as "Join Request frames". Are they the same thing?

I'll have a look at TTN and see if I can reproduce what you are seeing.

edit:

Just noticed an email from another user having the same problem.

[cjhdev]

You are right, the standard requires DevNonce to increment for each frame.

The "Technical Recommendations for Preventing State Synchronization Issues" lays out the reasons for why, and offers a workaround for the problem of running out of DevNonce increments.

[szemzoa]

Hi,

It's not just an issue with TTN network, you are right, this is a problem on my Chirpstack based gw on my table, and I saw this Join problem with a Loriot server too. My very similar workaround works for me on both gateways.

[cjhdev]

I've reproduced the problem in the integration test suite. This uses the Ruby wrapper and a headless ChirpStack instance.

I am expediting a fix based on frbehrens proof of concept.

[frbehrens]

I am expediting a fix based on frbehrens proof of concept.

Thanks! Please note, that I did not consider the random choice of devNonce.

[frbehrens]

With d443a90 the problem is fixed.
Thanks! I'll close the issue.