Great work on the FS project guys! I have a specific use case on a seasoned freeswitch machine that seems to be giving me problems based on SDP, working NAT configs, and freeswitch. First off, NAT works and my machines are resolvable by internal IP within the network and publicly via static public IP. My issue is not a functional NAT issue but how freeswitch assigns a private or public IP in SDP. I would like to control IP used in SDP at bridge, so that I can use private IP or public IP on demand where I want to instead of letting freeswitch insert it based on config settings. My scenario is all controlled via configs within freeswitch. All machines have private and public IPs but specific traffic must pass over private IP and in other places calls must bridge to another FS machine via external profile and public IP. Internal Profile= UPD 5080 External Profile= UDP 5060 1. A private call comes into freeswitch A over an MPLS to my internal SIP profile on UDP 5080. 2. The call then routes from freeswitch A via bridge to freeswitch B via public IPs on the external profiles using UDP 5060. Freeswitch B is only accessible via its public IP address. 3. Freeswitch B routes calls to a 3rd party IVR that gives callers the option to transfer back to Freeswitch A. When the caller selects to be transferred within the IVR freeswitch B makes a bridge back to freeswitch A using public IPs. 4. Freeswitch A receives the incoming call from freeswitch B public IP to public IP. 5. Freeswitch A uses another dialplan to route the call back out over the MPLS using private IP to private IP. I am running into SDP IP issues and how freeswitch is handing SDP based on where the call came from and where it needs to go to. I have spent some time playing with configs in vars and the profiles around rtp ports and ext-rtp nat, autonat, etc. I have SDP working how I need it to up to the last step (4 and 5 above) but I cannot get freeswitch to send its internal IP out in that last SDP session on bridge back over the MPLS. The MPLS only talks private ip to private ip and FSA is sending its public IP in SDP. This is where I am looking for an explicit way to control which SDP IP (local machine private or public) is sent out on bridge. Is this possible? If not, Is there a better way or alternative way to approach this scenario in freeswitch? Thanks guys