BLE broadcast with digital signature or encryption (asymmetric)

RE: BLE broadcast with digital signature or encryption (asymmetric)

Amanda Hsieh — Wed, 05 May 2021 11:43:01 GMT

Check out Beacon Transmitter Sample Application.

-Amanda H.

RE: BLE broadcast with digital signature or encryption (asymmetric)

MLai — Wed, 05 May 2021 09:55:38 GMT

Thanks. I think I am going to use ble 5.0 to broadcast the longer packet, is there any thing to start with, any example for ble 5.0 beacon broadcast? I am using nrf 52840 and softdevice s140 v6.1.1

RE: BLE broadcast with digital signature or encryption (asymmetric)

Amanda Hsieh — Wed, 05 May 2021 06:04:47 GMT

See ECDSA - Elliptic Curve Digital Signature Algorithm doc.

-Amanda H.

RE: BLE broadcast with digital signature or encryption (asymmetric)

MLai — Wed, 05 May 2021 02:54:50 GMT

May I know is there any algorithm that is 256 bit? And would like to know if I can use ECDSA

RE: BLE broadcast with digital signature or encryption (asymmetric)

Amanda Hsieh — Tue, 04 May 2021 12:11:33 GMT

Hi MLai,

I understand the question. But we do not provide support for any asynchronous signature algorithm shorter than 256 bit. So you would have to find something on your own then (not sure it is possible to get decent security though, there is probably a reason nothing shorter than 256 is used)

-Amanda H.

RE: BLE broadcast with digital signature or encryption (asymmetric)

MLai — Tue, 04 May 2021 09:26:16 GMT

I am not sure that is ECC the suitable one as I see the output ciphertext should be not less than 32 bytes, while for beacon broadcast, the payload should not more than 31 bytes.