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<?xml-stylesheet type="text/xsl" href="https://devzone.nordicsemi.com/cfs-file/__key/system/syndication/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>pairing / bonding in nrf51822..</title><link>https://devzone.nordicsemi.com/f/nordic-q-a/19315/pairing-bonding-in-nrf51822</link><description>Hai 
 i have the following queries about pairing / bonding in nrf51822. 
 
 can i retrieve the bonding information from flash memory. if so how can i do that..? 
 if a central is bonded with a peripheral. is it possible to spoof the information exchanged</description><dc:language>en-US</dc:language><generator>Telligent Community 13</generator><lastBuildDate>Tue, 31 Jan 2017 14:07:59 GMT</lastBuildDate><atom:link rel="self" type="application/rss+xml" href="https://devzone.nordicsemi.com/f/nordic-q-a/19315/pairing-bonding-in-nrf51822" /><item><title>RE: pairing / bonding in nrf51822..</title><link>https://devzone.nordicsemi.com/thread/74898?ContentTypeID=1</link><pubDate>Tue, 31 Jan 2017 14:07:59 GMT</pubDate><guid isPermaLink="false">137ad170-7792-4731-bb38-c0d22fbe4515:ebc700e3-44fb-4d9f-8afb-481bf097d30b</guid><dc:creator>Sigurd</dc:creator><description>&lt;p&gt;Hi,&lt;/p&gt;
&lt;p&gt;A1: The &lt;a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v12.2.0/lib_peer_manager.html?cp=4_0_1_3_1_8"&gt;Peer Manager&lt;/a&gt; module is used store and manage bonding, pairing and encryption. The Peer Manager stores and retrieves data autonomously and does not require you to manually store/load any data. However, if you want to manually read the bonding data you can use the API functions &lt;a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v13.0.0/group__peer__manager.html?cp=4_0_0_6_2_14_44#gabf148a0bb89fadfaae7f93bbda4e93ef"&gt;pm_peer_data_bonding_load()&lt;/a&gt; and &lt;a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v13.0.0/group__peer__manager.html?cp=4_0_0_6_2_14_47#ga84eebadf6d2f5531eb8d1e1157123b5d"&gt;pm_peer_data_load()&lt;/a&gt;.&lt;/p&gt;
&lt;p&gt;A2: When two BLE 4.2 devices are bonded they have derived a long-term key(LTK) based on a key exchange protocol. Based on this key the link between them is encrypted using AEC-CCM cryptography. If the spoofing-device does not know the key, it will not be able to decrypt the link. Using Man-in-the-Middle protection or OOB-pairing it is practical impossible for the sniffing-device to learn the key, and it will not be able to decrypt the link. See &lt;a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v12.2.0/lib_pm_usage.html?cp=4_0_1_3_1_8_2_1#lib_pm_usage_security"&gt;here&lt;/a&gt; on how to configure the different security parameters in the Peer Manager.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>