Hi, Thank you for the reply! I tried advertising udp port like this listen=udp:192.168.1.x:5060 advertise 182.70.xx.yy:5060. How to advertise RTP ports? Kamailio+RTPengine on a Centos s/m with a priv ip - 192.168.1.x Asterisk is on another CentOs s/m with a priv ip - 192.168.1.y pfsense on pub ip - 182.75.xx.yy PORT FORWARDING on pfsense- sip and rtp ports to kamailio+rtpengine server 192.168.1.x. How to make RTPengine listen on public interface-- 182.75.181.70? sip.conf ======== [general] context=external realm=192.168.1.y bindaddr=0.0.0.0:5080 tcpenable=no allowoverlap=no transport=udp,wss,ws srvlookup=yes qualify=yes directmedia=no canreinvite=no ;---------NAT SUPPORT--------- externip=182.75.xx.yy localnet=192.168.1.0/255.255.255.0 nat=yes ;nat=no //tried but no RTP ;nat=force_rport,comedia //tried but no RTP ;-----------RTP SUPPORT---------------- rtpkeepalive=30 disallow=all allow=gsm allow=ulaw allow=opus allow=alaw allow=g723 ================== and i am using asterisk realtime support for mysql to store peer details. With Regards, Arish Haque