Polycom - Network Address Translation
Network Address Translation (NAT) lets home office or small network environments use internal IP addresses for the devices within the network, while using one external IP address to communicate with the outside world (Wide Area Network). However, many Small Office Home Office (SOHO) routers provide NAT services that are not fully H.323 compliant.
Therefore, this solution is provided to enable the user make calls outside the internal network.
Note At this time, it is not possible to make video conferences calls within the internal network when using the NAT setting.
To make video conferencing calls within the network when using this solution, simply de-select the System is behind a NAT option and make the call. Re-select the System is behind a NAT option to re-activate this feature and make external calls.
Before You Start Configuring NAT
1. Determine your NATís external (WAN) IP address. This is the address assigned to your NATís external interface (connected to the Internet).
2. Determine the IP address of your ViewStation. This can be found on the System Information screen.
Setting up NAT
1. Go to the Quality of Service and Firewalls screen (System Info > Admin Setup > LAN/H.323 > H.323 > QoS).
2. Select Use Fixed Ports.
3. Select System is behind a NAT.
4. Enter the NATís external IP address into the NAT outside (WAN) address field.
Write down the Fixed TCP and UDP port numbers displayed on this screen. These numbers typically are the following default numbers:
TCP: 3230 to 3237
UDP: 3230 to 3235
5. In your NAT, reset the fixed ports from step 4 to be permanently open, and redirect them to the IP address of your ViewStation.
6. To accept incoming calls, open and redirect port 1720 to the IP address of your ViewStation.
Interoperability Check Point -
Calls through a Check Point firewall configured for H.323 may have no audio or video. To work around this, disable the H.323 traffic only protocol on Check Point and create new rules on the Check Point for TCP1720, TCP3230-3237, UDP 3230-3253.