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Coming soon |
1. STM32WB-WBA - Bluetooth® Low Energy (BLE) Filter Accept List
"Filter accept list is a list of addresses of peer devices that a device intends to interact with."
Security is the first reason.
| Bluetooth® Low Energy Filter Accept List |
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Filter Accept List helps reducing power consumption, there is no communication with devices not in the Filter Accept List.
Host specifies the required devices to communicate with.
Link Layer responds to devices in the Filter Accept List.
Interaction between layers are reduced.
Connection Accept List filters devices based on a list of Bluetooth addresses on both central and peripheral side.
If accept list is on the central side, scan results from non-listed devices are dropped and connecting to non-listed devices is not enabled.
If accept list is on the peripheral side, only listed devices can connect and receive scan responses (scan requests and connection requests from non-listed devices are dropped).
2. From advertiser point of view
As soon as a device advertises with the parameter "allow scan request - allow connect request from devices in white list"
(use of aci_gap_set_undirected_connectable, advertising filter policy = 0x03)
No HCI_LE_ADVERTISING_REPORT events are sent by the device but it answers to SCAN_REQ.
3. For advertiser and scanner
To add a device in white list, devices need to be bonded.
To know the addresses of the bonded devices: use of aci_gap_get_bonded_devices thanks to which we get the number of bonded devices, address types and addresses of bonded devices.
Then use aci_gap_configure_whitelist or aci_gap_add_devices_to_list.
The whitelist is written in RAM.
4. For scanner
An other possibility is to use for connection:
aci_gap_start_auto_connection_establish_proc
aci_gap_start_selective_connection_establish_proc
These commands allow the add of devices in whitelist at connection.
With aci_gap_start_selective_connection_establish_proc command, scanning_filter_policy parameter set to "ignore device not in the whitelist" allows the device to receive LE_ADVERTISING_EVENT from devices in the whitelist.
