New C40 cisco codec

Question

Hi,
I'm working for Industry Canada and we just received a new video conference system.  It is connected to a DSL line.  The video conferencing work perfect when we dial out.  But I have a issue when a external person try to dial me in, it can't connect.  I think there is a problem with local IP (modem) and dedicated IP (public IP).  I try to config. the modem but still experiencing problem with receiving calls.  
Anybody can help?          
Thank you    

Answer 1

For incoming call to Endpoint behind the FW/Router, you need to configure 1:1 NAT or port forwarding.
If firewall/router is H.323 awareness and support ALG, then you won’t need configure each port but most of home router will require manual port forwarding configuration.
For H.323 connection with C-series Endpoint, following ports will be use
Gatekeeper Discovery (RAS) – Port 1719 – UDP (not necessary for this case as not registering on GK).
Q.931 call Setup – Port 1720 – TCP
H.245 – Port Range 5555-6555– TCP
Video – Port Range 2326-2485 – UDP
Audio – Port Range 2326-2485 – UDP
Data/FECC – Port Range – 2326-2485 – UDP
Please note H.245 ports range is from 5555 to 6555 while port allocation configured as "Static".
If port allocation configured as "Dynamic", then port range is from 11000 to 20999.
If you modify port configuration (Static/Dynamic), codec must restart to affect configuration change.
Default RTP/RTCP port range for media is 2326 to 2485.
However this is configurable by "RTP Ports Range Start" and "RTP Ports Range Stop".