I am using freeswitch to dial calls through a dinstar GSM gateway with 32 sim cards. Calls works fine, and it goes out through any one of the free channels. However, the customer wants to know the cell number of the SIM card through which each call was made.
I am not able to see any options in Dinstar. It blindly returns whatever number I set in the origination_caller_id_number field. Is there any way to determine what is the caller ID that is being seen by the called party? The operator ignores any caller ID I set via origination_caller_id_number. It is always displaying the SIM card cell number.
I found a workaround. I enabled Portno header in Dinstar, so I get port-no with SIP messages. I just maintain a mapping between the phone-number and the port number in a DB. I can get the phone number using the port number. So I can manage with a single SIP trunk.