Data encrypted but also listened by sniffer

[Scarlet]

Hi, I'm developing an BLE application using nrf51822.

I have a BLE security issue to discuss. (Actually I don't have much network security background...)

In our application, we use pca10001 to transmit data. I modify ble_hrs sample code, and remove the bond manager and pstorage modules. This is because reducing the RAM (ZI-data) usage...

As my understanding, bond manager can save the "service discovery" information and other security information to flash with pstorage module.

[b]Our application want to send data packets with "encryption", and the sniffer (using pca10000) cannot recognize these data packet.[/b]

Before pca10001 starting advertising, the sniffer is on. When pca10001 start advertising, I select pca10001 and listen it.

When I try to use master control panel (another pca10000), I found the data will encrypted when I press the bond button (BLE_GAP_EVT_SEC_PARAMS_REQUEST event happen)

But the sniffer also can listen the data packet even the encryption flag is "Yes" in the wireshark. Is this normal? In my imagination, when the bond button is pressed, the sniffer cannot listen (recognize) this link anymore.

Any suggestion about this problem? Thanks!!

[thomas]

Maybe in your characteristic properties, you are using encryption without man in the middle protection.

BLE_GAP_CONN_SEC_MODE_SET_ENC_NO_MITM intead BLE_GAP_CONN_SEC_MODE_SET_ENC_WITH_MITM

[Scarlet]

Thanks Thomas :) More information:

As I read this: devzone.nordicsemi.com/.../how-to-enable-encryption-for-an-particular-characteristics-data I think I have to encrypted the link first, then I can read or write not open (secured) characteristics...

But I need bonding (or may not?) I removed the bonding manager and just set [ SEC_PARAM_BOND "1" ] in hrs sample code. I guess some ble events have to handle...

Any suggestion? Thanks again!