The Wireless Filter menu allows you to specify the MAC addresses of the only devices that will be allowed to connect on wireless interfaces. It is effectively a MAC Address whitelist for wireless access. (Default: Disabled).
MAC Address: Enter the 12-character MAC address of the client device you wish to allow access to the wireless network. Clicking Add will create a new row in the table in which you can add another MAC address.
Description: Here, you can enter an (optional) plain text description of the device. This is helpful for keeping track of the various client devices allowed to connect.
Finally, click Save for the changes to take effect.
Clicking the Virtual Wireless Interfaces link in the Notes section of this menu takes you to the Virtual Wireless menu. There, you can choose how and on which interface the Wireless Filter list of MAC addresses will work.
Note that for security purposes, Wireless Filter tends to prevent casual, inexperienced users from accessing a WiFi network. However, even in the most recent protocols/encryption, MAC addresses are not encrypted in WiFi traffic. Anyone with packet sniffing software, a wireless network adapter, and a little patience may be able to discover the MAC addresses of other clients on your network.