https://devzone.nordicsemi.com/f/nordic-q-a/37865/assigning-random-ble-mac-address---am-i-doing-it-rightHi I am developing a healthcare device which is paired via NFC. The NFC pairing is non-standard as it needs to work on iOS, I place records for a MAC and a service UUID on the tag. My app learns these from NFC then makes a pairing. The service ID isen-USTelligent Community 13Wed, 29 Aug 2018 09:34:39 GMThttps://devzone.nordicsemi.com/thread/146264?ContentTypeID=1Wed, 29 Aug 2018 09:34:39 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2d294a38-1ae9-4a35-a8be-16a085224780Sigurd<p>Hi,</p> [quote userid="73171" url="~/f/nordic-q-a/37865/assigning-random-ble-mac-address---am-i-doing-it-right"]1) Is there a better way?[/quote] <p>Another approach could be to use whitelist and <a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v15.1.0/lib_ble_advertising.html?cp=4_0_0_3_2_1">directed advertising</a>. Take a look at how this is done in the&nbsp;<a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v15.1.0/ble_sdk_app_hid_keyboard_pairing_nfc.html?cp=4_0_0_4_1_2_32">ble_app_hids_keyboard_pairing_nfc example</a>.</p> [quote userid="73171" url="~/f/nordic-q-a/37865/assigning-random-ble-mac-address---am-i-doing-it-right"]2) Are there any dangers in doing it the way I am (eg addresses considered invalid that centrals will refuse to connect to?)[/quote] <p>If you go for this approach, make sure that you are generating a valid random static address, where the 2 MSB is set to &#39;11&#39;. See <a href="https://devzone.nordicsemi.com/f/nordic-q-a/32877/ble-advertise-custom-mac-address-does-not-chance-the-last-2-msb/126893#126893">this</a> and <a href="https://devzone.nordicsemi.com/f/nordic-q-a/18877/i-want-to-change-the-ble-address#post-id-110344">this post</a>.</p><div style="clear:both;"></div>