Mandatory Authentication in Central RoleApp calls gatt_client_set_required_security_level (level > 0)App on A connects to BApp on A triggers GATT Client requestGATT Client request sentLTK available?yesnoSM_EVENT_REENCRYPTION_STARTEDstart encryptionre-encryptedyesnoSM_EVENT_REENCRYPTION_COMPLETE(ERROR_CODE_SUCCESS)GATT Client request sentApp receives GATT ResponseSM_EVENT_REENCRYPTION_COMPLETE(error)App receives GATT_QUERY_COMPLETE eventwith ATT_ERROR_BONDING_INFORMATION_MISSINGSM_EVENT_PAIRING_STARTEDstart pairingpairing success?yesnoSM_EVENT_PAIRING_COMPLETE(ERROR_CODE_SUCCESS)GATT Client request sentApp receives GATT ResponseSM_EVENT_PAIRING_COMPLETE(error)level >= 3yesnoApp receives GATT_QUERY_COMPLETE eventwith ATT_ERROR_INSUFFICIENT_AUTHENTICATIONApp receives GATT_QUERY_COMPLETE eventwith ATT_ERROR_INSUFFICIENT_ENCRYPTION;