RE: OOB DHkey request failure

Vidar Berg — Tue, 26 Nov 2019 13:03:39 GMT

Hi,

I'd recommend using the nrf_ble_lesc module from SDK 15.3.0 or SDK 16.0.0. if you aren't doing it already. It should make it easier to set up custom OOB channels according to the release notes:

nrf_ble_lesc (part of the Peer Manager) now supports the LESC OOB pairing mode.
The ble_nfc_pairing_reference_c example demonstrates how to pass the OOB data to the module.

[quote user=""]So, the central has to have an OOB flag set to on, but the peripheral does not?[/quote]

The initiator can decide which pairing algorithm to use when using secure connections OOB pairing and when OOB and MITM flag are both set to 0 on the peripheral. Decision tables can be found in core spec 5.0, vol3, part H, section 2.3.5.1, table 2.6 and 2.7.

But have you considered passkey or numeric comparison pairing as an alternative? They also provide MITM protection. Maybe you can "display" the passkey through the USB as the Glucose Application does over UART. I think it's easier to implement.