iOS auto disconnect after 30s

[Tuan Nguyen <tuan.nguyen@xxxxxxxxxxxx>]

Hi there,

I am using bluez 5.50 to write an application to communicate with iOS
app via BLE.
the python advertisement and gatt server work well but when I tried to
change gatt security method from encrypt-read/write to read/write, my
iOS app alway disconnect after 30s.

Using btmon, i found a error related to Insufficient Authentication.
Also try to test with bluez 5.47, the issue does not happen.

Thanks

Tuan Nguyen