LE Security Mode 1 Level 4 是什么？ 在CC2640r2f下如何设置？

某安全认证关于BLE的要求如下:

BLE must use LE Security Mode 1 Level 4 only

请问,什么是LE Security Mode 1 Level 4 , 在CC2640r2f下如何设置?

- LE Security Mode 1
1. No security (No authentication and no encryption)
2. Unauthenticated pairing with encryption
3. Authenticated pairing with encryption

- LE Security Mode 2
1. Unauthenticated pairing with data signing
2. Authenticated pairing with data signing

更具体的要求请参考蓝牙规范，在蓝牙技术联盟可以下载