User's Manual

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BTTracer Protocol Analyzer User’s ManualCATC Version 1.0
11.4 BT Neighborhood
The BT Neighborhood status box displays information about known
Bluetooth™ devices. This command is accessible through the View menu
in the menu bar. Three types of data are displayed: Device Address, Class
of Device (COD), and the Bluetooth™ Clock Frequency for each
discovered device. The expected Bluetooth™ clock frequency is 3200 Hz
+/- 250 PPM.
11.5 Encryption
Bluetooth encryption is a multi-staged process that provides devices with
secure, encrypted communications. The process begins with a device
prompting the user for a Personal Identification Number (PIN). When the
right PIN is entered, the Slave begins an encryption setup dialogue with the
Master. At the beginning of this dialogue, the Slave and the Master agree
on a Link Key. A Link Key is a 128-bit value that the two devices use for
authentication. When the Slave and Master agree on a Link Key, the Slave
then negotiates for the transfer of the Encryption Key from the Master
device. The Encryption Key is used to encrypt and decrypt messages. Once
the Encryption Key is transferred, both devices use it to encrypt all
subsequent communications.
In order for BTTracer to decode encrypted traffic, it needs the Link Key for
each Master-Slave connection for which encryption will be used. If you
know the Link Key, you can enter the Key into the Encryption Options
dialog box. If you do not know it, you give BTTracer the PIN for a device