BLE 4.2 support

[Roei]

Hi,

I'm working on nrf52840. As far as I understand, that device supports connection to peers with BLE 4.2 at least.

However, I'm able to connect via my phone, which contains BLE 4.1.

1) How is it possible?

2) Do I have an option to recognize the BLE version of my peer, after connection?

Thanks!

[Simonr]

Hi

The nRF52840 supports Bluetooth 5.0. The Bluetooth specification allows all BLE devices to connect to one another even if they're not the same version. Devices supporting newer versions of BLE will not be able to use the features specific to the newer versions when connected to older devices, but there's nothing stopping them from connecting to older BLE versions.

Best regards,

Simon

[Roei]

In terms of security, I would like that devices with BLE under 4.2 will not be able to connect.

Can I solve this issue with defining MITM protection?