How to reject or filter Mobile station from my service.

[habibur333]

Hi everyone.
On subscribers.conf file i used
regexp=.*
thats why it is now on open registration and any mobile station can easily connect with yatebts.
At present i have no sim card writer . is there any way to block some mobile station or reject there connection without using sim card? Or any  filtering system to maintain the connection of expected mobiles and ban the others.Thanks

[Monica Tepelus]

You set regexp to a value matching only the sims you use