BPA low energy Devices Under Test

You can select the ComProbe BPA low energy analyzer for sniffing Bluetooth low energy communications on available devices.

Note: Frontline BPA LE supports Bluetooth low energy features through Bluetooth 4.2, except optional extended packet length.

The default value in the LE Device drop down is Sync with First Master. Devices in the LE Device Database may be selected. Once a device is selected or if any other change is made to the Devices Under 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

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

2. Enter a PIN or out-of-band (OOB) value for pairing.

This optional information offers alternative pairing methods.

Click here to learn more about these possible pairing values.
 One of two pieces of data allow alternative pairing:

1. PIN is a six-digit (or less if leading zeros are omitted) decimal number.

2. Out-of-Band (OOB) data is a 16-digit hexadecimal code which the devices exchange via a channel that is different than the le transmission itself. This channel is called OOB.

For off-the-shelf devices we cannot sniff OOB data, but in the lab you may have access to the data exchanged through this channel. 

Click here to see how to capture data after completing the configuration.

Sniffer Diagnostics: Checking this box will record communications traffic between ComProbe software and the ComProbe BPA low energy hardware. Most often used in conjunction with Frontline Technical Support instructions should the user have problems with their hardware. Checking this box will not affect capture, analysis, or display of data.

Filter out ADV packets for Non-Configured devices: Checking this box will filter out advertising packets from devices not specified in the LE Device field. If "Sync with First Master" has been selected in the LE Device field checking this box will have not affect. the purpose of this option is to reduce the advertising traffic in situations where there are many devices; advertising traffic can clutter the captured data with unnecessary packets.

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