Hello Users, <br>Good Morning,<br>What are Type of the NAT is used for OpenSER for production , OpenSER is inside the NAT&nbsp; (router/firewall )<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1)&nbsp;&nbsp; I tested with 2 SJ phones and 2 cisco ATA phones, UAC&#39;s are in
Behind&nbsp; the NAT,&nbsp; UACs are in the Same N/w with one public_address, <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; SJ phone show the NAT type is <font size="4"><span style="font-weight: bold; font-style: italic;">Symmetric NAT</span></font> 
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; this case is Working Fine,<br>For example :<br>
[Behind the NAT1 ] &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [Behind the NAT2] &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [Behind the NAT1 ]<br>
SJphone -------------------------------&gt;&nbsp;&nbsp; OpenSER---------------------&gt; ATA phone <br><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 2) When SJ phones or HardPhones are in Different network&nbsp; behind the NAT of the OpenSER server, 
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; here SJ phone shows the&nbsp; <font size="4"><span style="font-weight: bold; font-style: italic;">Port Restricted&nbsp; core&nbsp; NAT  </span></font><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Here&nbsp; media is not is signaling at all , in this Case....
<br><br>For example :<br>[Behind the NAT1 ] &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [Behind the NAT2] &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; [Behind the NAT3 ]<br>SJphone -------------------------------&gt;&nbsp;&nbsp; OpenSER---------------------&gt; ATA phone <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br>SIP&nbsp; NAT Traversal support only Symmetric &nbsp; NAT ,&nbsp; ? 
<br><br>Then How to solve this issue ? Please&nbsp; Help ? <br clear="all"><br>-- <br>Thanks and Regards<br>Ravi Prakash Sunkara		<br><a href="mailto:ravi.sunkara@hyperion-tech.com">ravi.sunkara@hyperion-tech.com</a> 	<br>M:+91 9985077535
<br><a href="http://www.hyperion-tech.com">www.hyperion-tech.com</a><br>Client and Parent company :- <a href="http://www.august-networks.com">www.august-networks.com</a>