https://devzone.nordicsemi.com/f/nordic-q-a/9956/clean-way-to-deal-with-a-central-not-bonding-pseudo-denial-of-serviceiOS&#39;s auto connect introduces a number of unpleasant corner cases that can be difficult to deal with. One annoying error path is if you delete the bond data on the peripheral but not on the iOS device. When iOS auto-reconnects, it will not do any IOsen-USTelligent Community 13Wed, 28 Oct 2015 11:34:18 GMThttps://devzone.nordicsemi.com/thread/36946?ContentTypeID=1Wed, 28 Oct 2015 11:34:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a22b37e0-ec0d-4eb7-a780-7b0302bfd72fPetter Myhre<p>You cannot force the central. You can send a security request with sd_ble_gap_authenticate(), but iOS doesn&#39;t respond to that.</p> <p>When the peripheral has lost the bond that you will end up in variant 2 in <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s130.api.v1.0.0/group___b_l_e___g_a_p___p_e_r_i_p_h___e_n_c___m_s_c.html?cp=2_7_2_1_0_2_1_0_10">this</a> MSC. So after you reply with sd_ble_gap_sec_info_reply(NULL) you could do a disconnect. It seems that to do this requires you to modify the Device Manager library a bit.</p> <p>I guess it doesn&#39;t solve your problem, but it is an alternative to a timeout.</p><div style="clear:both;"></div>