[SR-Users] kamailio rtp connection

Good day all I hope I’m on the right place to ask the question. I’m a newbie to kamailio and have a little problem understanding how to set kamailio correctly. Scenario: VoIP Supplier (IP:161.161.252.20{Private Net}) à Connect via routing to Kamailio Server(155.155.16.2 eno2{private Net}),Kamailio Server(187.221.197.252 eno1{public facing})àconnect to PBX(public IP set in dispatcher) à connect to RTP server(Public IP) Now the problem is that if you call in Number(a)161.161.252.20 <mailto:Number@161.161.252.20> is send to kamailio, kamailio then sends it down to dispatcher IP and that PBX responds directly back via rtp server to 161.161.252.20. The 161.161.252.20 IP is private and cannot be reached from the cloud and vice versa . How do I get kamailio to be the middle man between 161.161.252.20 and RTP server(all traffic must go via the kamailio server) Is there specific modules I must load. I’m running Kamailio 4.4 Any help would be muchly appreciated. Regards Pieter