INSUFFICIENT_AUTHENTICATION with Master Control Panel on PC with Dongle

[medamarko]

Hi All,

Im planing to use NRf51 as a BT Central mode device and to do some simple things (like Immediate Alert control). First i tried things with dongle and Master control panel on my PC.

I have a problem to successfully bond to one BLE device. Ble device support BT 4.2 and it has bonding mechanism in place. When i press bond in Master control panel im getting:

[12:05:04.4] BondToDevice()

[12:05:04.4] Bond already exists with

05FF005B0200

But in upper area of screen in Device info panel Bonded is saying: False. Most of chars i can read without problem but i cannot write to any of them. When i try to write im getting:

[11:58:25.7] Could not update handle 0x0015 with new value. Error code: INSUFFICIENT_AUTHENTICATION

In Options->Security i tried: No keyboard or display/Keyboard only as the device has display just one button for enable bonding. Same result with any option.

If i use lightblue app on iOS i can do successful write and get the alarm to happen.

Do you have any ideas? Thanks.

[run_ar]

Try to delete all bonds before you connect to the device, then bond again. Bonding is needed if you get the insufficient authentication error. If the bond information is lost on one side, you will also have to delete this on the peer before you bond again. You also have to make sure the security requirements for your characteristics matches the bonding capabilities of your device.

[medamarko]

Thanks on response, already tried with clearing bonding list from both sides. Sorry if this is stupid question but how i can make sure that security requirements are matching bonding capabilities? Is there any way i can read it out or check with some tool?

[run_ar]

If you look at the service initializing procedure you can see that we set cccd and attr properties like this: BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm); //for read permissions BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm); // for write permissions

The example above is open but you can also require bonding with or without MITM using these: BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM
BLE_GAP_CONN_SEC_MODE_SET_ENC_WITH_MITM

If it says WITH_MITM your device has to support bonding with MITM (passkey) for you to be able to write to this characteristic.

[sbailes]

Where would that go? (The read and write_perms) Would it go in gap_params_init? When I try putting it there it stops advertising.

[run_ar]

No, this is when you initialize characteristics. See the tutorial on how to add those here.

[sbailes]

What if I don't have a characteristic that supports the read and write permissions? My application uses DFU and NUS services and that's it.