we are facing an issue ,when we called a user,and if the user is in a active data session,voice call get missed.
It says user phone is switch off.
this happens in 2G only,when the Phone is 3G it is okay.
You cannot page a MS in a data session, unless :
1. the phone is able to listen to the PCH while in transfer mode
2. the Gs interface (MSC – SGSN) is implemented
3. your BSS is able to coordinate the CS Paging towards MS in transfer mode.
For 3G, there is no such problem because data and voice are handled by the same network. In 2G, the voice is handled by MSC, the data by SGSN.