User's Guide

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HT81x User Guide
NAT Settings
If you plan to keep the HT81X within a private network behind a firewall, we recommend using STUN
Server. The following three settings are useful in the STUN Server scenario:
1. STUN Server (under advanced settings webpage) Enter a STUN server IP (or FQDN) that you may
have, or look up a free public STUN Server on the internet and enter it on this field. If using Public IP,
keep this field blank.
2. Use Random SIP/RTP Ports (under advanced settings webpage) This setting depends on your
network settings. Generally, if you have multiple IP devices under the same network, it should be set
to Yes. If using a public IP address, set this parameter to No.
3. NAT traversal (under the FXS web page) Set this to Yes when gateway is behind firewall on a private
network.