https://devzone.nordicsemi.com/f/nordic-q-a/21587/how-to-make-51822-not-discoverable-to-phoneHi, I have 52832(ble_app_multilink_central 12.2) which is connected to 5 51822 (experimental_ble_app_blinky) modules. How to make 51822 not discoverable or not connectable to phone/tablet(android/ios )?en-USTelligent Community 13Tue, 25 Apr 2017 08:42:08 GMThttps://devzone.nordicsemi.com/thread/84765?ContentTypeID=1Tue, 25 Apr 2017 08:42:08 GMT137ad170-7792-4731-bb38-c0d22fbe4515:0811e7e2-371c-458c-98e4-658028f497b1Petter Myhre<p>The common way to this is to whitelist the central in the five peripherals.</p> <p>Then the peripheral will only accept connection requests from that specific central, and filter out any other.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/84764?ContentTypeID=1Mon, 24 Apr 2017 16:11:14 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1fa33b17-3292-4b8b-aeee-15d41eca074aWojtek<p>Yes, that is why i proposed those 3 possible solutions. They are not perfect, but will work for most cases. Not all though ofc.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/84763?ContentTypeID=1Mon, 24 Apr 2017 15:37:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:75c2b806-3f45-4301-ac67-94c59fa69a02sword<p>There is no problem between 52832 and 51822 ,works fine.When 51822 is not connected ( not in a range ) to master it can be connected by phone.I don&#39;t want this.</p> <p>I don&#39;t want any connection from the outside to the current working system.It must be closed system</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/84762?ContentTypeID=1Mon, 24 Apr 2017 14:39:33 GMT137ad170-7792-4731-bb38-c0d22fbe4515:afe949bf-2e5d-479e-b1f4-1d56181037f8Wojtek<p>What you can do is:</p> <ul> <li>directed advertising on those 5x 51822 (so only 52832 receives adverts)</li> <li>whitelisting 52832 for connection to those 51822</li> <li>blacklisting phones/tablets (stupid solution)</li> </ul><div style="clear:both;"></div>