Transient Application Key (TAK)#
Overview#
The Transient Application Key (TAK) feature provides enhanced security for Bluetooth LE connections between the Localization Reader and Device applications. TAK is a one-time use symmetric key that must be pre-shared between devices before establishing a connection. Once used, the key is automatically erased per specification requirements. This guide provides out-of-the-box commands ready for copy-paste into TeraTerm.
Prerequisites#
Ensure both applications are compiled with TAK enabled (gAppUseTAK_d = 1) and gAppTAKAdvID_c matches on both sides. The default configuration supports up to 4 TAK entries (gConnTakMaxEntries_c = 4).
In order for Peripheral to allow passing LTK request (coming from an unbonded device) to the application, gBleHostAutoRejectLtkRequestForUnbondedDevices_c must be set to FALSE in the loc_user_device application.
Because TAK is not considered sufficient method for an attribute which requires encryption, all encryption-related flags from the database must be removed.
Check gatt_db.h, on the loc_user_device and remove the flags gPermissionFlagWriteWithEncryption_c and gPermissionFlagReadWithEncryption_c.
Quick Setup#
Setup on Localization Reader#
tak 0 00112233445566778899aabbccddeeff
sb
Setup on Localization Device#
tak 0 00112233445566778899aabbccddeeff
sb
For Subsequent Connections#
Since TAK is erased after use, set a new key before the next connection:
tak 0 112233445566778899aabbccddeeff00
Typical Console Output#
