Mesh proxy re connection and sequence number

Question

Hi 
 I re open an old ticket to know about changes in the Android Mesh Library 
 https://devzone.nordicsemi.com/f/nordic-q-a/45553/is-sequence-number-and-transaction-id-equal 
 I see that, now, the Mesh SDK for nrf52 keep a good track of sequence number and IV index. But we are still facing issues when a phone re connect to a proxy node. 
 To get the sequence number, we send a message to set a new proxy filter type (here blacklist 0x0000) and receive a new sequence number. 
 But sometime the board is not accepting the filter messages. 
 Also, the board is not accepting any message after the app came to foreground. when the app is in background, it is connected to the board all the time. so here we need to restarting the board before being able to send any new message. 
 Is there any way to get the board's sequence number without sending filter messages? 
 
 thank you very much.

Hung Bui · Accepted Answer

Hi Olivier, From Roshan: 
 As of now, the spec does not state anything for a scenario like you have specified, but still there is a way around it. You can still use the backed up json to retrieve the last provisioner and change the provisioner address to something new and this should let you continue with a new sequence number if that address is not in use. 
 
 Sequence number is important in mesh it's used for encryption, identifying a unique messages from each device and also to protect devices from replay attacks. Our sample app will clear the local app data will erase everything just like any other app out there and it's only a sample app. You can improve your end user app to handle these case better. Like I mentioned before this is why we left the API open and provide our users with the flexibility just for purposes like this.

Mesh proxy re connection and sequence number

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