PLANET VGW-400FO - Manual (Page 43)

4-Port SIP Internet Telephony Gateway
VGW-400 Series
5.4 NAT Traversal
The VGW-400 series supports the following NAT traversal methods when it is placed behind the router.
NAT Traversal:
Item Explanation
Disable Disable NAT traversal features
STUN (Type 1,2)
Enable STUN for NAT traversal. Since STUN can be used only
for type 1 and type 2 NAT servers, it is recommended to use
this option. When STUN client detects the current NAT is type
3, it stops the STUN feature operation.
— STUN Server: STUN Server IP address
STUN (All)
No matter which NAT type server is used, STUN is always used
for NAT traversal.
— STUN Server: STUN Server IP address
UPNP
Enable UPnP client for NAT traversal. Please note that the IP
sharing box (or router) needs to support uPnP feature.
Behind NAT
Use DMZ for NAT traversal
IP Sharing Address: public IP sharing address. You need to
specify the port mapping or DMZ for all required ports
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