Bluetooth rebonding options

[DaniSi]

Hey,

I would like to know if its somehow possible to rebond if the central device (nrf52) has deleted the bonding information  about a device and then this deleted peripheral (phone which is still bonded) wants to connect?

In a practical case if this case occurs the phone will at a connect attempt just immediately disconnect.

Thank you

[Hung Bui]

Hi Danijel, 

I assume you are using nRF5 SDK ? 

You can have a look at this case: devzone.nordicsemi.com/.../pairing-and-bonding-after-deleting-synchronization

[DaniSi]

Hi Hung,

yes we use the nrf52 SDK

this we have already implemented and it works in the case if you delete the bonding information from the phone, but not the nrf device.

If its the oposite (bonding information are still on phone, bonding information are deleted from nrf device), no rebond will be issued.

[Hung Bui]

Hi Danijel, 

Sorry I misread your question. 

In that case it's up to the phone to decide to allow a new bonding request or not. 

In many phone it's not allowed. It's related to a security risk that attacker can spoof an address of your device and force the phone to make a new bond. 

The easiest way of solving this is to ask the phone's user to delete bond information on the phone.

Please check the sniffer trace to see if the central actually send any bond request or it's only the phone sending encryption request. There could be a chance that if the central send bonding request before the phone sending encryption request the phone would accept to have a new bond (some phones do that).