TA400/800 User Manual
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more than one IP address.
To change the user agent parameter of asterisk, the
default is ―TA FXS Gateway‖; you can change it if
needed.
If you would like to use G.729 codec, please buy the
license and enter the license key here.
2) NAT
Figure 5-5 NAT Settings
Table 5-5 Description of SIP General Settings
STUN (Simple Traversal of UDP through NATs) is a protocol for assisting
devices behind a NAT firewall or router with their packet routing.
The STUN server allows clients to find out their public address, the type of
NAT they are behind and the internet side port associated by the NAT with
a particular local port. This information is used to set up UDP
communication between the client and the VOIP provider and so establish
a call.
The IP address that will be associated with outbound SIP messages if the
system is in a NAT environment.
Alternatively you can specify an external host, and the system will perform
DNS queries periodically.
This setting is only required when your public IP address is not static. It is
recommended that a static public IP address is used with this system.
Please contact your ISP for more information.
External
Refresh
Interval
Used to identify the local network using a network number/subnet mask
pair when the system is behind a NAT or firewall.
Some examples of this are as follows:
―192.168.0.0/255.255.0.0‖: All RFC 1918 addresses are local networks;
―10.0.0.0/255.0.0.0‖: Also RFC1918;
―172.16.0.0/12‖:Another RFC1918 with CIDR notation;
―169.254.0.0/255.255.0.0‖: Zero conf local network.