Thanks Andres for your answer, the problem I&#39;m having is that I&#39;m not being able to register an extension from outside of the firewall. I would appreciate if someone could put me on the right path. I&#39;m still not sure if I have to enable the NAT module or the DOMAIN module  and add the external IP or something else, this are the SIP messages I have captured:<div>
<br></div><div><div>T <a href="http://190.244.125.41:13674">190.244.125.41:13674</a> -&gt; <a href="http://172.16.99.2:5060">172.16.99.2:5060</a> [AP]</div><div>REGISTER sip:67.152.18.231;transport=tcp SIP/2.0.</div><div>
Via: SIP/2.0/TCP 192.168.15.231:13618;branch=z9hG4bK-d8754z-e24b1938012d8901-1---d8754z-;rport.</div><div>Max-Forwards: 70.</div><div>Contact: &lt;sip:1104@192.168.15.231:13618;rinstance=00ac7562f8530813;transport=TCP&gt;.</div>
<div>To: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;.</div><div>From: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;;tag=bd13120b.</div>
<div>Call-ID: Y2M0MTQ4YjFhNmM0NTZjMzAzYWE1OGQwZjViYzJlNDc..</div><div>CSeq: 1 REGISTER.</div><div>Expires: 3600.</div><div>Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, NOTIFY, MESSAGE, SUBSCRIBE, INFO.</div><div>Supported: replaces.</div>
<div>User-Agent: Bria Professional release 2.4 stamp 49381.</div><div>Content-Length: 0.</div><div>.</div><div><br></div><div>##</div><div>T <a href="http://172.16.99.2:5060">172.16.99.2:5060</a> -&gt; <a href="http://190.244.125.41:13674">190.244.125.41:13674</a> [AP]</div>
<div>SIP/2.0 401 Unauthorized.</div><div>Via: SIP/2.0/TCP 192.168.15.231:13618;branch=z9hG4bK-d8754z-e24b1938012d8901-1---d8754z-;rport=13674;received=190.244.125.41.</div><div>To: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;;tag=863f16b592640a21218764f3174429d9.6a1f.</div>
<div>From: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;;tag=bd13120b.</div><div>Call-ID: Y2M0MTQ4YjFhNmM0NTZjMzAzYWE1OGQwZjViYzJlNDc..</div><div>CSeq: 1 REGISTER.</div><div>
WWW-Authenticate: Digest realm=&quot;67.152.18.231&quot;, nonce=&quot;TeUBwE3lAJRMHoOxnzL57scTzxhDfpO9&quot;.</div><div>Server: kamailio (3.1.3 (i386/linux)).</div><div>Content-Length: 0.</div><div>.</div><div><br></div><div>
#</div><div>T <a href="http://190.244.125.41:13674">190.244.125.41:13674</a> -&gt; <a href="http://172.16.99.2:5060">172.16.99.2:5060</a> [AP]</div><div>REGISTER sip:67.152.18.231;transport=tcp SIP/2.0.</div><div>Via: SIP/2.0/TCP 192.168.15.231:13618;branch=z9hG4bK-d8754z-ad5e03279628ca35-1---d8754z-;rport.</div>
<div>Max-Forwards: 70.</div><div>Contact: &lt;sip:1104@192.168.15.231:13618;rinstance=00ac7562f8530813;transport=TCP&gt;.</div><div>To: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;.</div>
<div>From: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;;tag=bd13120b.</div><div>Call-ID: Y2M0MTQ4YjFhNmM0NTZjMzAzYWE1OGQwZjViYzJlNDc..</div><div>CSeq: 2 REGISTER.</div><div>
Expires: 3600.</div><div>Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, NOTIFY, MESSAGE, SUBSCRIBE, INFO.</div><div>Supported: replaces.</div><div>User-Agent: Bria Professional release 2.4 stamp 49381.</div><div>Authorization: Digest username=&quot;1104&quot;,realm=&quot;67.152.18.231&quot;,nonce=&quot;TeUBwE3lAJRMHoOxnzL57scTzxhDfpO9&quot;,uri=&quot;sip:67.152.18.231;transport=tcp&quot;,response=&quot;65ea2f6596115a5ac76ec391f7e9c93e&quot;,algorithm=MD5.</div>
<div>Content-Length: 0.</div><div>.</div><div><br></div><div>##</div><div>T <a href="http://172.16.99.2:5060">172.16.99.2:5060</a> -&gt; <a href="http://190.244.125.41:13674">190.244.125.41:13674</a> [AP]</div><div>SIP/2.0 408 Request Timeout.</div>
<div>Via: SIP/2.0/TCP 192.168.15.231:13618;branch=z9hG4bK-d8754z-ad5e03279628ca35-1---d8754z-;rport=13674;received=190.244.125.41.</div><div>To: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;;tag=065c4e5ee3769aabfc84958a193ed91c-3b57.</div>
<div>From: &quot;Lucas&quot;&lt;<a href="mailto:sip%3A1104@67.152.18.231">sip:1104@67.152.18.231</a>&gt;;tag=bd13120b.</div><div>Call-ID: Y2M0MTQ4YjFhNmM0NTZjMzAzYWE1OGQwZjViYzJlNDc..</div><div>CSeq: 2 REGISTER.</div><div>
Server: kamailio (3.1.3 (i386/linux)).</div><div>Content-Length: 0.</div><div>.</div><div><br></div><div><br></div><div>Thanks in advance,</div><div><br></div><div><br></div><div>Lucas</div><br><div class="gmail_quote">On Tue, May 31, 2011 at 10:13 AM, Andreas Granig <span dir="ltr">&lt;<a href="mailto:agranig@sipwise.com">agranig@sipwise.com</a>&gt;</span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Hi,<br>
<div class="im"><br>
On 05/31/2011 03:04 PM, Lucas Alvarez wrote:<br>
&gt; Hi, if I want to register clients from outside of my local network, do I<br>
&gt; have to enable the domain module and add the external IP as a new domain?<br>
<br>
</div>Depends on your configuration. The domain module just provides the<br>
functionality to check - based on the domain table - whether the domain<br>
part in From, R-URI or any pseudo-variable is present in the table.<br>
<br>
If you want your user A to be visible and valid as A@your-domain and<br>
A@your-ip and possibly A@anything, then you should set &quot;use_domain&quot; in<br>
usrloc module (and probably others which you already use) to &quot;0&quot; to not<br>
check for the domain part at all.<br>
<font color="#888888"><br>
Andreas<br>
<br>
</font><br>_______________________________________________<br>
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list<br>
<a href="mailto:sr-users@lists.sip-router.org">sr-users@lists.sip-router.org</a><br>
<a href="http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users" target="_blank">http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users</a><br>
<br></blockquote></div><br></div>