Hi, we have here four 3cxphone clients behind a pfSense firewall. They work with 3cxtunnel. In this case only one port has to be opened... Can somebody tell me which ports have to be opened for the comversations? My 3cxphone (for windows) have the following settings: "general network settings" RTP Ports: 40000-40049 (UDP) Local SIP Port: 5060 (UDP) Tunnel: 5090 (UDP) For this reason I think all the ports have to be opened for both directions: LAN & WAN Am I right? Because of the NAT 5090 or 5060 has to be forwarded to the LAN-Client. How can I however made it, if there are more clients? The pfSense-Router is behind an SFR Modem. The port 5090 has for this reason to be routed from the modem to the Router, does not it? Thanks a lot for your help. I.