API to make a call to the gsm mobile numbers

[ragu.]

i am doing pjsip project what are the api s to be used to make a call to gsm mobile numbers . now i could make a call to ekiga.net accounts.

[petrib]

You can't have a VoIP call terminate as a real GSM call, unless you cooperate with a network operator/carrier, or without your own PBX.

[ragu.]

cant understand tell me more clear

[petrib]

pjsip is a VoIP, Voice-Over-IP (Internet Protocol as in TCP/IP) SIP (Session Initiation Protocol) stack, as you presumably know.

You can make a pjsip caller connect to another compatible VoIP/SIP callee, but without a proper phone network exchange (PBX, Private Branch eXchange), you cannot make a VoIP/SIP call connect to an actual mobile (or fixed line) network number. In order to do that, you would need to cooperate with a service provider (such as a network operator/carrier) with the required infrastructure technology (servers and phone exhanges, etc.) or lease and operate your own phone exchange (PBX).

There is no way you can achieve this connectivity by developing client software alone (pjsip or equivalent).