Version 7.2 147 Mediant 1000B Gateway & E-SBC
User's Manual 12. Network
The figure below illustrates the NAT problem faced by SIP networks when the device is
located behind a NAT:
Figure 12-5: Device behind NAT and NAT Issues
12.7.1.1 Configuring a Static NAT IP Address for All Interfaces
You can configure a global (public) IP address of the router to enable static NAT between
the device and the Internet for all network interfaces. The device replaces the source IP
address for media of all outgoing SIP messages sent on any of its network interfaces to
this public IP address.
The following procedure describes how to configure a static NAT address through the Web
interface. You can also configure it through ini file (StaticNATIP) or CLI (configure voip >
sip-definition settings > nat-ip-addr).
 To configure a single static NAT IP address:
1. Open the Gateway General Settings page (Setup menu > Signaling & Media tab >
Gateway folder > Gateway General Settings).
Figure 12-6: Configuring Static NAT IP Address
2. In the 'NAT IP Address' field, enter the NAT IP address in dotted-decimal notation.
3. Click Apply, and then reset the device with a save-to-flash for your settings to take
effect.
Note: The feature is applicable only to the Gateway application.