CC2650STK: Is the scan response message encrypted ?

Calin Pop

Part Number: CC2650STK
Other Parts Discussed in Thread: CC2650, CC2640R2F

Hi,

I want to send sensitive data over scan request messages. Since it is a radio signal and it can be intercepted by anyone, my question is that the message is encrypted like messages that are transmitted when the device are pairing (connected).

over 8 years ago

0 YiKai Chen over 8 years ago

Guru 735705 points

No, it's not. However, you can encrypt/decrypt it in application layer.

0 Calin Pop over 8 years ago in reply to YiKai Chen

Prodigy 190 points

Thanks.
From CC2640R2F I want to authenticate some CC2650 sensor tags according to the data sent, address, etc, which send advertising messages.
Is there a way to ensure that a external ble device from my system can't copy the information on which authentication is based and "trick" my system ?

0 YiKai Chen over 8 years ago in reply to Calin Pop

Guru 735705 points

As I mentioned in my previous reply, you can use your own AES128 to encrypt advertising so others cannot decrypt it.

0 Calin Pop over 8 years ago in reply to YiKai Chen

Prodigy 190 points

If the external device intercepts the encrypted data and sends them further,the data still being encrypted, how can I be sure that the device from which I receive data is external or internal, since both devices send the exact same encrypted data ?
I am not interested in the content of the received information but the correct identification of the source of the information.

0 YiKai Chen over 8 years ago in reply to Calin Pop

Guru 735705 points

From my point of view, you cannot avoid this case.

0 Calin Pop over 8 years ago in reply to YiKai Chen

Prodigy 190 points

Thanks.

So, there is no way to be 100% sure about the source of a message using BLE devices.

0 YiKai Chen over 8 years ago in reply to Calin Pop

Guru 735705 points

What do you mean to ask “ there is no way to be 100% sure about the source of a message using BLE devices?”

0 Calin Pop over 8 years ago in reply to YiKai Chen

Prodigy 190 points

If I have a simple_central application ( CC2640R2F) and a simple_broadcaster (CC2650 STK), how can I be sure if the advertising message received by simple_central is a message from my CC2650 STK and not from another BLE device with the same address, advertising data and type etc ?

0 YiKai Chen over 8 years ago in reply to Calin Pop

Guru 735705 points

There’s no guarantee for this case.

0 JXS over 8 years ago in reply to Calin Pop

TI__Guru** 105180 points

Calin Pop said:

If I have a simple_central application ( CC2640R2F) and a simple_broadcaster (CC2650 STK), how can I be sure if the advertising message received by simple_central is a message from my CC2650 STK and not from another BLE device with the same address, advertising data and type etc ?

Hello Calin,

This is why you would encrypt the messages (i.e., ADV payload data) at the application layer. The assumption is you have distributed your encryption keys in a secure manner and thus any attempt to "spoof" your device would be thwarted since the attacker would not have your key. Note that to prevent replay attacks, many implementations including BLE link layer encryption, utilize a counter mechanism to prevent such attacks.

For more details on what security enablers are available for the CC2640R2F, please see

Best wishes

Bluetooth®︎

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CC2650STK: Is the scan response message encrypted ?