Any experiences about BLE security with Arduino?

I have been reading a lot about BLE security lately. But, I have found only a bunch of links talking about doing something concrete around ble security:

  1. 2. ble security vulnerabilities
  2. 3. Open source approach towards building ble security:

Apart from these, I couldn't find resource to learn further. Turning towards this community to learn more practical implementations for developers. What do you do in terms of security implementations? I would love to get your opinion on Key20's approach as well.