<p>Bogdan, normally the script uses nat_traversal/client_nat_test("3") . I have tested flags 7 & 15 and NAT was still not detected; also tested all the flags incrementally for nathelper/nat_uac_test("127") and also not detected. </p>
<p>I'm tending to think it is something out of the norm with the client's mobile network or the client itself and is a special case.</p>
<p>The script below enables the client to register (effectively client_nat_test("7")). Not yet known how this will affect other clients.</p>
<pre><code>route(CHECKTOPVIA);
if (isflagset(RFC1918) || client_nat_test("3")) {
force_rport();
fix_contact();
if (is_method("REGISTER") ) {
$avp(received_uri) = $source_uri;
setbflag(NAT_BFLAG);
} else {
setflag(NAT);
}
if (!has_totag() && is_method("REGISTER|INVITE|SUBSCRIBE")) {
if (proto==UDP) {
nat_keepalive();
} else {
setflag(TCP_PERSISTENT_FLAG);
}
}
}
</code></pre>
<p><code><br>
route[CHECKTOPVIA] {<br>
if (pcre_match("$(hdr(via)[0])",".<em>UDP (172.\b([1][6-9]|[2][0-9]|[3][0-1])\b.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b).</em>") || pcre_match("$(hdr(via)[0])",".<em>UDP (10.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b).</em>") || pcre_match("$(hdr(via)[0])",".<em>UDP (192.\b([0-9]|[1-9][0-9]|1[0-6][0-8])\b.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b.\b([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\b).</em>") ) {<br>
setflag(RFC1918);<br>
} <br>
}<br>
</code></p>
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