Problem description: The
video conference terminal is mapped to the public network, and the terminal equipment deployed in the branch venue calls through H323 IP. As a result, a black screen appears and the connection is directly dropped after 20 seconds.
The cause of the problem: The
main reason is that the video conference terminal of the main conference site did not receive the audio and video data stream of the terminal of the branch conference site for 20 seconds, and actively hung up the call. The main problem is that the Connect of the H323 protocol carries the intranet IP address, and the terminal equipment of the branch venue cannot access the intranet IP address, which causes the audio and video stream channel to fail to be established successfully.
Solution:
1) Enable the ALG function on the corporate network export equipment (router, firewall) of the main venue, mainly for the ALG function of the H323 protocol. The ALG function can temporarily convert the internal network IP and port into a public network IP and port.
2) Enable the static NAT function on the video conferencing terminal of the main venue, allowing Connect to carry the public IP address from the beginning.