Thanks for your reply! I found nat_traversal.so in /usr/local/lib64/kamailio/modules/ directory. But didn't find a switch in pcscf.cfg or kamailio.cfg. So how can I open nat_travesal module? -- View this message in context: http://sip-router.1086192.n5.nabble.com/User-offline-tp148166p148176.html Sent from the Users mailing list archive at Nabble.com.