pairing / bonding in nrf51822..

[iqbalpalemad]

Hai

i have the following queries about pairing / bonding in nrf51822.

1. can i retrieve the bonding information from flash memory. if so how can i do that..?
2. if a central is bonded with a peripheral. is it possible to spoof the information exchanged by them, especially the mac address of central.

thank you

[Sigurd]

Hi,

A1: The Peer Manager module is used store and manage bonding, pairing and encryption. The Peer Manager stores and retrieves data autonomously and does not require you to manually store/load any data. However, if you want to manually read the bonding data you can use the API functions pm_peer_data_bonding_load() and pm_peer_data_load().

A2: When two BLE 4.2 devices are bonded they have derived a long-term key(LTK) based on a key exchange protocol. Based on this key the link between them is encrypted using AEC-CCM cryptography. If the spoofing-device does not know the key, it will not be able to decrypt the link. Using Man-in-the-Middle protection or OOB-pairing it is practical impossible for the sniffing-device to learn the key, and it will not be able to decrypt the link. See here on how to configure the different security parameters in the Peer Manager.