connecting to specific device

RE: connecting to specific device

Edvin — Fri, 15 Mar 2019 11:17:30 GMT

Naralasetty Praneeth

I am not following you now.

RE: connecting to specific device

Naralasetty Praneeth — Wed, 13 Mar 2019 14:06:09 GMT

@Edvin

Not ble devices i am asking that for other android app

RE: connecting to specific device

Edvin — Wed, 13 Mar 2019 13:54:39 GMT

You seem to misunderstand how advertising works. It is not possible to make advertisements invisible for other BLE devices. I have already suggested other ways that you can send data to only one device. You NEED to connect.

RE: connecting to specific device

Naralasetty Praneeth — Wed, 13 Mar 2019 12:47:37 GMT

@Edvin then how can we achieve that process and please give me any code so that it will be useful

thankyou

RE: connecting to specific device

Edvin — Wed, 13 Mar 2019 12:46:56 GMT

Not achieveable.

RE: connecting to specific device

Naralasetty Praneeth — Wed, 13 Mar 2019 10:25:15 GMT

@Edvin

if it can be achieved please give any code if available so that i can add to my code

RE: connecting to specific device

Naralasetty Praneeth — Wed, 13 Mar 2019 10:12:10 GMT

@Edvin my beacon should only advertise to specific devices can it be acheived using preshared irk and no need of encryption so by advertising to specific devices no third person can see the beacon inofrmation

RE: connecting to specific device

Edvin — Wed, 13 Mar 2019 09:49:42 GMT

Hello,

As I tried to say, having bonded and advertising using a whitelist doesn't encrypt the data. If you want to encrypt your data, you have to either connect and encrypt the link. Once this link is encrypted, you can store the encryption keys (LTK - long term keys), which is done when bonding. However, the advertisements are not encrypted.

There is no good way to encrypt advertisements. You could of course encrypt it manually, but that is a weak security. The reason for this is that you don't have two way communication, so it is not possible to cycle through keys or include counters to enable playback protection.

I recommend that you use connection instead, and store bonding data.

RE: connecting to specific device

Naralasetty Praneeth — Tue, 12 Mar 2019 14:28:08 GMT

@Edvin Yes i want to encrypt my data so that only specific app or specific device can decrypt and see that data... Is it possible by doing with pre shared irk so that it advertises to only specific devices with same irk

RE: connecting to specific device

Edvin — Tue, 12 Mar 2019 14:09:14 GMT

Hello,

It is possible to use directed advertising, and thus, devices that follow the BLE spec will "not see" your packets, but they are by no mean protected against malicious devices. The packets are on the air, and they are not encrypted. They just have a bit saying that "I am only speaking to devices that I have been connected to before", and thus, encouraging the other devices to ignore these advertisement packets. They may also try to connect to the device, but typically the device would reject these connection requests.

What exactly are you looking for? Do you want to encrypt your data? If so, I suggest you consider actually creating a connection and encrypting the link instead. We have a few examples in the SDK doing this.

Best Regards,

Edvin