Sony SGPT21 - Manual (Page 24)

About Bluetooth(R) Security
Bluetooth wireless technology has an authentication function that allows you to determine with whom you choose
to communicate.
With the authentication function, you can prevent any anonymous Bluetooth devices from accessing your tablet
device. The first time two Bluetooth devices communicate, a common passkey (a password required for
authentication) should be determined for both devices to be registered. Once a device is registered, there is no
need to re-enter the passkey.
Your tablet device will be detected by other Bluetooth devices, only when it is set to allow detection by other
Bluetooth devices. You can set the time to accept the detection, or whether or not to allow reception after both
devices are connected.