some kind of BT device should be required pairing key exchange.( eg, 4 or 6 digit numbers )
That means some user scenarios may need user interaction(input or confirm the key numbers ) during first discovery phase.
If there were a number of BT devices near the user device, user device will try to request pairing key exchange regardless the BT device owner.
I think it doesn't make sense and it can cause very serious user experience problem. ( security, privacy, etc. )
So, I have added the separation of pairing exchange from the discovery procedure.
Then the IoTivity tries to find resources from already paired BT devices provided each platform