We need to develop SIP gateway. It should be able to pass voice calls incoming over SIP through the Gateway.
Further details will be discussed through chat.
Please the atteched file.
4 freelancers are bidding on average $676 for this job
Please contact to discuss details. I'm nowy entirely sure if it's possibile at this point. However when I know details IT may clarify ( if simpler than it looks at first point mayby price could be reduced)
I have several years of experience with SIP Projects. I can build for you a SIP Gateway with the transfer call functionality that can be as simple from Sip Servlet to more complexity escenario