[SR-Users] kamailio.cfg : behind the NAT (listen and advertise) understanding

Hi Dear I am trying to understand how "listen" and "advertise" work for sip signaling purpose ( corebooks : listen <http://www.kamailio.org/wiki/cookbooks/5.4.x/core#listen> and advertise ) Flow : kamailio behind NAT using softphones on private and public networks. - kamailio : Network : IPv4_private 192.168.1.6 / IPv4_public kamailio.cfg : listen=udp: IPv4_private: 5060 advertise IPv4_public : 5060 - uac (softphone) : zoiper, microsip, cisco spa508g USE CASE : I 'd like to force all softphone on the same local network to reach kamailio through a public ip address. ??? QUESTION : Do I need to REGISTER on IPv4_private address of Kamailio OR REGISTER on IPv4_public address of kamailio or DEFINE another "listen" with another PORT WITHOUT "advertise" for softphone on same kamailio network ? listen=udp: IPv4_private: 5060 advertise IPv4_public : 5060 listen=udp: IPv4_private: 5066 Do I need to use "kamctl ps" to verify which interface is listening on port ? Thanks in advance Best Regards, Youssef BOUJRAF Email: yboujraf(a)gmail.com