https://devzone.nordicsemi.com/f/nordic-q-a/105755/what-happens-to-a-ble-connection-when-i-update-the-advertised-servicesHello, I need help to make one service discoverable only in a specific situation. My problem is that I can&#39;t be sure if an already stablished connection would be affected if I try to change the advertised data on-the-fly. For example: I have 2en-USTelligent Community 13Fri, 17 Nov 2023 10:29:32 GMThttps://devzone.nordicsemi.com/thread/456121?ContentTypeID=1Fri, 17 Nov 2023 10:29:32 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e4a704d8-75e9-4fa8-9249-6c1db4fddc83Hung Bui<p>Hi,</p> <p>There is no direct&nbsp;dependency&nbsp;between the service UUID (s) that you advertise and what you have in your attribute table.&nbsp;</p> <p>They belong to different BLE layers. Advertising packet is handled by GAP and the attribute table (the services) is in GATT.&nbsp;</p> <p>So if you simply update the advertising packet using&nbsp;ble_advertising_advdata_update() there will be no change in the attribute table or to the connection you already have.&nbsp;</p> <p>But you will need to add service Y to the GATT attribute able at some point, right ? Then if you add the new service to the GATT table, the peer device in your current connection, may do a service discovery and may find the new service. <br />In any case the current connection will not break.&nbsp;</p><div style="clear:both;"></div>