Hello, why you need to hide the ip in the contact if it is in sdp? You don't really achieve topology hiding with it. If you use record_route()/loose_route() in kamailio, the sip packets related to active calls should come always to kamailio and kamailio will forward them to freeswitch. Cheers, Daniel On 09/03/14 10:04, jay binks wrote: So im using Kamailio as a load balancer and proxy in-front of a few Freeswitch boxes. Im not going to use RTP Proxy, as my FS boxes will be public on the internet ( Direct RTP connection is fine ). I want ALL SIP to go via Kamailio, but the issue im running into is that the SIP Contact header has the FS IP address in it in some cases. ( 180's etc ) Every bit of documentation I can find about re-writing the Contact header is geared around NAT, and thats not what im trying to do here.. Can anyone give some pointers on how to basically topology hide the FS boxes on the SIP front but leave their IP in the SDP. im going to have the firewalls setup so the SIP Can ONLY come from kamailio, so its quite important I get this all right. Any pointers would be appreciated. Thanks Jay _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing listsr-users@lists.sip-router.orghttp://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users -- Daniel-Constantin Mierla - http://www.asipto.comhttp://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda Kamailio World Conference - April 2-4, 2014, Berlin, Germanyhttp://www.kamailioworld.com _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list sr-users(a)lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users