How can able to connect my device to only one device using whitlelist?

[NIDHIN K]

i want to connect my nrf51822 device to only one phone for secure,now its able to connect all the phone so its not secure, i think its possible using whitelist so anybody pls explain how to use whitelist with one sample code.

[NIDHIN K]

Now my device can able to connect all the phone so its not secure, so i want to connect my device to my phone only or may be one more phone.