Hi, I'm currently using 3CX v8 with a fritzbox 7170 + a Grandstream GXV3000 and X-Lite softphone. I'm using Voipbuster.com and budgetphone.nl as sip providers and everything works fine in the LAN. VOIP/SIP voice via WAN also works fine. I'm now trying to use video telephony (H263) over wan via 3cx pabx. Situation explanation, 3cxpabx -<> WAN <> - sip client over wan using 3cxpab I have the following ports open on my fw: 5080 udp for sip 5090 tco for 3cx tunnel 9000-9015 udp for sip providers externally My question is do I need to open extra ports, RTP for example for video? And if yes should they be forwarded to the 3cx server or to the sip device, grandstream in this case or x-lite softphone?