TTN -> How many JoinRequests are stored

Hello,

from a security point of view I found something in relation to replay attacks against LoRaWAN and it seems like storing the latest n JoinRequest messages is needed to prevent an replay attack against the network server - in our case the TTN.
Does anyone know how many JoinRequest messages are stored by TTN until somebody could replay an old JoinRequest in order to establish the same session details?
Seems like this information is hidden somewhere inside TTN and not available to public?

Kind regards

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Actually I’m refering to the paper by Gildas Avoine -> https://www.semanticscholar.org/paper/Rescuing-LoRaWAN-1.0-Avoine/e21cb378a92b30f8ebb4252ebdd2e2f378f0507d chapter “3.1.2 Targeting the NS”
-> “According to the specification, the NS must keeptrack of “a certain number” of received DevNonce values in order to prevent replay attacks, withoutclarifying if this means all values or a few of them.”
But how big is the number of DevNonces (and therefore JoinRequests) in case of TTN? Or are there any other countermeasures in place?

yes I understand… there are several papers on theoretical LoRaWAN attack vectors.
let’s say there haven’t been a succesfull LoRaWAN replay ‘attack’ on TTN as far as I know.
at least not publiced

I don’t know, but I’m sure there are :sunglasses: