Direct advertising with unbonded Android phone's IRK

[Pureer]

I was using NRF52832 and s132 v6.0.

I have Android phone's IRK and I have added the Android phone into the identites list manually.

After doing the direct advertising to Android phone.Why can't nrf52832 be connected ?

I have noticed that some comments in the devzone said "You can't be connected with direct advertising without bonding".But why?I think if I get the IRK ,and add to the identites list,it should be connected .It can accord to the BT core Vol 6 Part D 5.4 .

Maybe should I add the Android phone into the peer_list manually too?

[ovrebekk]

Hi

Why can't you bond to the phone that you want to connect to?

If you don't bond with the phone first you don't have any guarantee that the phone will accept the connection. 

Best regards
Torbjørn

[Pureer]

Hi,

My goal is to establish a connection without human involved. And if there has many peripherals,it will take a lot time to find specific peripheral. So I think direct advertising is a good way.

[ovrebekk]

Hi 

Who decides then which phone should be connected to which peripheral, if there is no human to control the procedure?

Is this controlled from the cloud?

Best regards
Torbjørn

[Pureer]

ovrebekk, this is a bit like nfc pairing,I call it sound wave pairing but data is one-way transmission, people take up the phone and close to the peripheral, peripheral will get the IRK.

By the way , whitelist works fine ,direct advertising dosen't work.

[ovrebekk]

Hi

It sounds like white listing is the way to go then. If you include the BLE address and OOB pairing data in the sound wave transmission you can use this information to set up the white list in the peripheral. 

If you want the phone to only try to connect to peripherals that have received the sound wave information, you could include some information here that needs to be reflected in the advertise packet sent from the peripheral (for instance you can generate a random number that needs to be included in the advertise packet, and only try to connect to advertisers that include this). 

Best regards
Torbjørn

[Pureer]

ovrebekk,whitelist with manual IRK is working fine,do you know why direct advertising didn't work with manual IRK? What did I miss in my code above?According to BT core Vol 6 Part D 5.4 ,it should work.

[ovrebekk]

Hi 

How are you scanning for the device on the phone side?

I don't know if nRF Connect it set up to show direct advertisers, but I will check with the developer when he is in office. 

Best regards
Torbjørn

[Pureer]

Hi ovrebekk ,

     In my phone Oneplus3 Android8.0,nrf52832 with direct advertising didn't show up in nRF Connect's list, but I didn't close the device tab ,so I can push the connect button.

[ovrebekk]

Hi 

The problem in this case is that the directed advertising packet will not be reported to the application as a normal advertising packet, so the phone would have to know about the device in some other way. 

This is outside our control since it is handled by the Bluetooth stack in the phone. 

Best regards
Torbjørn