Re: [RFC bluetooth-next 20/20] 6lowpan: bluetooth: add new implementation

[Johan Hedberg <johan.hedberg@gmail.com>]

Hi Alex,

On Tue, Jul 19, 2016, Alexander Aring wrote:
> mhhh, I am not a bluetooth expert. What really means "periodically
> change is RPA" and how is this done in the Linux bluetooth?
> 
> When "changing the RPA" happens, does that mean the all connections will
> be lost (unregister interface). Then the previous connections will be
> recreated (register interface) with a complete different MAC address?

Connections aren't lost when the random address is changed. That's why
we track the hci_conn->init_addr and hci_conn->resp_addr. The way this
is dealt with e.g. the Security Manager protocol is that the connection
creation address *is* the address for the remote device throughout the
entire connection, no matter what happens to the local and remote random
address during the connection. I would expect 6LoWPAN do do something
similar.

What was still unclear to me (maybe I missed it in the thread): does the
6LoWPAN for LE spec require using the connection creation address or the
identity address? If it would be the latter then that's something that
will never change and the whole interface recreation issue goes away.

Johan