<html>
  <head>
    <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  </head>
  <body text="#000000" bgcolor="#FFFFFF">
    <tt>Indeed,</tt><br>
    <pre class="moz-signature" cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a class="moz-txt-link-freetext" href="http://www.opensips-solutions.com">http://www.opensips-solutions.com</a></pre>
    <div class="moz-cite-prefix">On 07.08.2015 20:08, Nabeel wrote:<br>
    </div>
    <blockquote
cite="mid:CA+vx6KKfk6KyUby8o+iW=6tKMCrN2KUwHeDwvuJ0WqCANQiiKg@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div>You mean like this, right?</div>
        <div><br>
        </div>
        <div>if (is_method("REGISTER"))</div>
        <div><br>
        </div>
        <div><span class="Apple-tab-span" style="white-space:pre"> </span>{</div>
        <div><span class="Apple-tab-span" style="white-space:pre"> </span>if
          (   0 ) setflag(TCP_PERSISTENT);</div>
        <div><br>
        </div>
        <div>                <span
            style="font-family:arial,helvetica,sans-serif">setbflag(SIP_PING_FLAG);</span></div>
        <div><br>
        </div>
        <div><span class="Apple-tab-span" style="white-space:pre"> </span>if
          (!save("location"))</div>
        <div><span class="Apple-tab-span" style="white-space:pre"> </span>sl_reply_error();</div>
        <div><br>
        </div>
        <div><span class="Apple-tab-span" style="white-space:pre"> </span>exit;</div>
        <div><span class="Apple-tab-span" style="white-space:pre"> </span>}</div>
        <div><br>
        </div>
        <div><br>
        </div>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">On 7 August 2015 at 17:52,
          Bogdan-Andrei Iancu <span dir="ltr">&lt;<a
              moz-do-not-send="true" href="mailto:bogdan@opensips.org"
              target="_blank">bogdan@opensips.org</a>&gt;</span> wrote:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0
            .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div text="#000000" bgcolor="#FFFFFF"> Hi Nabeel,<span
                class=""><br>
                <pre cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a moz-do-not-send="true" href="http://www.opensips-solutions.com" target="_blank">http://www.opensips-solutions.com</a></pre>
              </span>
              <div>On 07.08.2015 19:39, Nabeel wrote:<br>
              </div>
              <blockquote type="cite">
                <div dir="ltr"><font face="arial, helvetica, sans-serif">[........]</font><span
                    class=""><br>
                    <div><font face="arial, helvetica, sans-serif">Bogdan,</font></div>
                    <div><font face="arial, helvetica, sans-serif"><br>
                      </font></div>
                    <div><font face="arial, helvetica, sans-serif">Regarding
                        UDP, I realised that the UDP port could not be
                        in LISTEN state and this was probably preventing
                        my server from fully opening that port.  Running
                        nmap on that port showed result "open|filtered",
                        unlike with TCP which showed fully open.  I am
                        not running any firewalls on my server, so this
                        seems to be the default behaviour of my network.</font></div>
                  </span></div>
              </blockquote>
              <font face="arial, helvetica, sans-serif">A bidirectional
                traffic through the NAT will keep the NAT pinhole open,
                while a unidirectional one may not. This is the
                advantage of the SIP pinging versus simple UDP pinging.</font><span
                class=""><br>
                <blockquote type="cite">
                  <div dir="ltr">
                    <div><font face="arial, helvetica, sans-serif"><br>
                      </font></div>
                    <div><span
                        style="font-family:arial,helvetica,sans-serif">I
                        would like to clarify one thing.  You mentioned
                        adding setbflag(SIP_PING_FLAG) before doing
                        save(), but in my config file I don't see save()
                        anywhere, there is only this line: "if
                        (!save("location"))".  Where exactly do I add
                        this line?</span><font face="arial, helvetica,
                        sans-serif"><br>
                      </font></div>
                  </div>
                </blockquote>
              </span><font face="arial, helvetica, sans-serif">exactly.</font><br>
              <br>
              <font face="arial, helvetica, sans-serif">Regards,<br>
                Bogdan<br>
              </font><br>
            </div>
          </blockquote>
        </div>
        <br>
      </div>
    </blockquote>
    <br>
  </body>
</html>