BLE Encryption without any

[Jusang Kim]

I'm using the nRF52DK and S132. Is it possible to encrypt a link without any pairing, bonding and authentication process ? Please show me the way how to implement with the APIs if it is. Thank you.

[Youssif]

According to the Bluetooth Specification: "If at least one authentication has been performed, encryption may be used". So no, this is not possible. The reason for this is that ediv and rand (along with the other keys) are distributed during the pairing process (specifically phase 3, Key Distribution).

Have a look at the Core Specification Version 5.0, Vol 3, Part H, Section 2.4. It covers the details of pairing and encryption.

The only workaround is if the two devices were bonded (i.e. if the devices were previously paired, and the keys distributed have been stored by the slave). The previously distributed keys can then be used to encrypt the connection.

[Jusang Kim]

Thank you for your reply.

Firstly let me check the specification that you mentioned about. I'll let you know if i have a further question.