Teledyne LeCroy Merlin - Users Manual - Manual (Page 164)

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Merlin Protocol Analyzer User’s Manual CATC SW Version 2.0
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 Merlin 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 Merlin the PIN for a device and
allow Merlin to discover the Link Key on its own. Once Merlin has the Link
Key, it can capture the rest of what it needs by listening to the Master and
Slave devices as they negotiate for the Encryption Key.
Configuring Merlin for Encryption
For Merlin to successfully decrypt traffic Merlin needs to be given the PIN
or Link Key for each Master-Slave connection before the Link Key is
created. If recording is begun prior to the creating the Master-Slave
connection, Merlin will be able to obtain the encryption key and decode
encrypted traffic.
The following steps show how to configure Merlin for encrypted traffic.
Note Be sure to begin the following process prior to connecting your Slave device to
the Master or Merlin will not be able to capture the Link Key.
Step 1
Select View >Device List
The Device List appears.