Yeastar Technology MyPBX U520, Installation Manual

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MyPBX U5XX Administrator's Guide
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· User Agent
To change the user agent parameter of asterisk, the default is “MyPBX”, you
could change it if needed.
Figure 6-59 SIP Settings-NAT
2) NAT
Note : Configuration of this section is only required when using remote
extensions.
· Enable STUN
STUN (Simple Traversal of UDP through NATs) is a protocol for assisting devices
behind a NAT firewall or router with their packet routing.
· STUN Address
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.
· External IP Address
The IP address that will be associated with outbound SIP messages if the system
is in a NAT environment.
· External Host
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 be used with this system. Please
contact your ISP for more information.
· External Refresh Interval