FrontLine BPA LOW ENERGY, Hardware User Manual

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Test tab, the toolbar save button becomes available. Clicking on this button will save the current Devices
Under Test settings that will be available the next time you open ComProbe BPA low energy analysis.
To begin sniffing Bluetooth low energy simply click the red Start button on the datasource toolbar.
Specifying the LE Device Address
You may specify the LE device you are testing by typing in or choosing its address (BD_ADDR). You can type it
directly into the drop down, or choose it from the existing previous values list in the drop down.
Alternatively you can open the LE Device Database tab, right-click on any device in the list, and click on
Select LE Device in the pop-up menu. The selected device's BD_Addr and Nickname will appear in the
LE Device field.
To enter the device manually type the address - 12 digit hex number (6 octets). The "0x" is automatically
typed in the drop down control.
Note: If one device changes its address and the other device does not, then select the
device address that does not change for the LE Device Address field.
Once you have the devices address identified, the next step is to identify the Encryption.
LE Encryption
Figure 3.2 - BPA low energy Devices Under Test LE Encryption
1. Enter the
Long Term Key
for the
LE Encryption
.
The Long Term Key is similar to the Link key in Classic. It is a persistent key that is stored in both devices
and used to derive a fresh encryption key each time the devices go encrypted.
Click here to learn more about the Long Term Key .
In LE, the long term key is generated solely on the slave device and then, during pairing, is distributed to a
master device that wants to establish an encrypted connection to that slave in the future. Thus the long term
key is transmitted over the air, albeit encrypted with a one-time key derived during the pairing process and
discarded afterwards (the so called short term key).
The long term key is directional, i.e. it is only used to for connections from the master to the slave (referring
to the roles of the devices during the pairing process). If the devices also want to connect the other way
round in the future, the device in the master role (during the pairing process) also needs to send its own long
term key to the device in the slave role during the pairing process (also encrypted with the short term key of
course), so that the device which was in the slave during the pairing process can be a master in the future and
connect to the device which was master during the pairing process (but then would be in a slave role).
Since most simple LE devices are only ever slave and never master at all, the second long term key exchange
is optional during the pairing process.
Note: f you use Copy/Paste to insert the Long Term Key , ComProbe software will auto
correct (remove invalid white spaces) to correctly format the key
Chapter 3 Configuration Settings TELEDYNE LECROY
Frontline BPA low energy Hardware & Software User Manual 15