Hello Users, Good Morning, What are Type of the NAT is used for OpenSER for production , OpenSER is inside the NAT (router/firewall ) 1) I tested with 2 SJ phones and 2 cisco ATA phones, UAC's are in Behind the NAT, UACs are in the Same N/w with one public_address, SJ phone show the NAT type is Symmetric NAT in Display... this case is Working Fine, 2) When SJ phones or HardPhones are in Different network behind the NAT of the OpenSER server, here SJ phone shows the Port Restricted core NAT Here media is not is signaling at all , in this Case.... SIP NAT Traversal support only Symmetric NAT , ? Then How to solve this issue ? Please Help ? -- Thanks and Regards Ravi Prakash Sunkara ravi.sunkara(a)hyperion-tech.com M:+91 9985077535 Client and Parent company :- www.august-networks.com