LSC Security Benefits with Static Passkey

[moon.kim]

Hi. 

I try to implement LESC using nRF52810.

But I use a Static passkey because my device doesn't have a keyboard or display.

One question is, is LESC more secure than Legacy when using a Static passkey?

I understand that using a Static passkey is not safe from MITM attacks. Is LESC safe from MITM attacks when using Static Passkey?

I've been pondering for days and couldn't come to a conclusion.

[Simonr]

Hi

If you're using Static passkey either way, I think you should use legacy pairing, as the LESC module isn't designed to be used with a static passkey. The legacy mode will be susceptible to eavesdropping, but a MITM attacker won't be able to decrypt the connections of already bonded devices.

Best regards,

Simon