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Right-click External Elements and select New External Gateways.
Right-click External Gateways and select New External Gateway. The IMG 1010 - External Gateway pane appears.
In the Gateway Signaling Protocol field select SIP.
In the Gateway IP Address, enter the IP address of the gateway.
In the Gateway Transport Type field, select either UDP, TCP, or TLS.
Refer to IMG 1010 - External Gateway (section "Gateway Transport Type") for more information.
Change the Gateway Remote Port if required. Default = 5060.
If Gateway Registration is required, change the Gateway Registration field to Yes. Default = No.
To validate a range of IP addresses for multiple gateways, use the Gateway Mask field.
Use the Trusted and Privacy fields to configure SIP Privacy. See IMG 1010 - Configuring SIP Privacy for more information.
See the IMG 1010 - External Gateway pane reference for details.