Network Address Translation - Yealink SIP-T2 SERIES Administrator's Manual

Enter the desired port scope in the TCP Port Scope field.
3.
Click Confirm to accept the change.
4.
A dialog box pops up to prompt that settings will take effect after a reboot.
Click OK to reboot the phone.
5.

Network Address Translation

Network Address Translation (NAT) is essentially a translation table that maps public IP address
and port combinations to private ones. This reduces the need for a large number of public IP
addresses. NAT ensures security since each outgoing or incoming request must first go through
a translation process.
Configuring Advanced Features
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