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GSM Gateway User Manual
www.allo.com Version 2.0 27
NAT Settings
Navigate through
Setup
>
Advanced
>
SIP Global Settings
In this NAT Settings, user can select Stun Server IP or External IP function. These functions can
help your VoIP device working properly behind NAT.
Figure 122: NAT Settings
NAT Settings
NAT
NAT option is checked, when the GSM Gateway is behind the
Router/Firewall. Select either Stun Server IP or External IP.
Default:
disabled
Stun Server IP
If the GSM Gateway is behind a non-symmetric NAT router, it
may be necessary to use STUN to allow GSM Gateway to reliably
communicate via IP through the router. Enter a STUN server IP
address or domain name in the STUN Server field. For a list of
public STUN servers, please Refer to:
External IP
Enter the NAT Traversal IP address i.e. Public IP Address of your
internet, to communicate with Public Network when GSM
Gateway is behind the NAT. This IP address will substitute in all