BLE bonding

[Roei]

Hi,

As far as I understand, every connection establishment has to start with advertising.

Event if I have already connected and bonded to a peer, after disconnection I have to start advertising in order to connect to this peer again.

Am I right?

In that case - what is the meaning of bonding here? Shouldn't the peers connect automatically again without advertising/direct advertising? Do I have another option?

Thanks!

[Roei]

Thanks, you helped me a lot!

I still don't understand how exactly the IRK works. Can you give me an example, how the first peer can recognize the second peer, using IRK, after the second one changed it's address?

[Einar Thorsrud]

The IRK is Identity Resolving Key, which gives a hint. When a device using a resolvable address changes the address, that is derived from the IRK. And it is also possible to do the reverse: check an address to see if it has been derived from a specific IRK, which is done by the peer that has the IRK after bonding. The exact details of how the resolution works is black magic to me (cryptography), but there is no need to understand the math in order to use it.