We use Polycom Telepresence m100 to test with our other systems. The systems we try to call are off site and they have either HDX 4000 or HDX 8000 depending on the site. They all have IP addresses and the calls are H323. They can't call us because of the way we are set up so we initiate all calls.
The calls connect (we can see the time in the bottom left of the screen and the call logs state that we connected), but we get no audio or video from the far site (just a blank screen). However the far site can see us (not sure if they can hear us because we mute the microphone). We have tested with more than one of our systems and the same thing happens. After about 15 seconds or so of being connected, we get the following message: "A firewall on the computer or network may be blocking the audio or video sent from the far end. Please read the troubleshooting in help and adjust the firewall settings to allow inbound audio and video."
We think it's a port issue but we put all of the ports that we know of in our router and still get no audio or video from the far site. But if we call the Polycom test number in Israel, it connects and we can see their video (they don't have any audio at that site). We are confused as to why we can make an international call and get video but we cannot get video from systems we call in the US. Also the sites we are trying to call are working correctly because they use it often. Any suggestions?
Your firewall MUST understand H.323 protocol for this to work. (OR, you must put your M100 machine in the DMZ and let it have the public IP address). Most business Firewall/Routers has the ability to handle H.323, it just has to be enabled.
Opening just the ports is not sufficent to allow bi-directional video/audio traffic when using H.323.
You could try my test site too.. 126.96.36.199 or 188.8.131.52 . It has the advantage that it will try to send your video back to you. This will help you know if your video is getting out (and back).