https://devzone.nordicsemi.com/f/nordic-q-a/19514/connection-without-encryptionDocumentation specifies levels of security mode 1, and first level means that connection is without any encryption. But how it is possible? Every connection starts with pairing, and even if devices were bonded without exchange LTK or CSRK, the pairingen-USTelligent Community 13Mon, 06 Feb 2017 21:16:43 GMThttps://devzone.nordicsemi.com/thread/75838?ContentTypeID=1Mon, 06 Feb 2017 21:16:43 GMT137ad170-7792-4731-bb38-c0d22fbe4515:33c18bc2-77d5-49f4-b356-f6600b616cfbRK<p>No. Every connection does not start with encryption, every connection starts with a simple connection and unless a procedure is started to initiate encryption, it stays unencrypted.</p><div style="clear:both;"></div>