title: WCF + SSL wsDualHttpBinding or netTcpBinding
body: <p>I need to create a self-hosted WCF service.
  I need secure duplex connection between client and server through Internet.</p>
  
  <p>I read some documents of WCF and found that the netTcpBinding is suitable for intranet application, because the SSL is only point 2 point. If it is an internet application, the connection must not be point 2 point, am I correct? so SSL in transport security with netTcpBinding is not suitable?</p>
  
  <p>so what combination should I use to create a secure duplex internet application?
  thank you very much.</p>
  
  <hr>
  
  <p>I have tried <a href="http://www.codeproject.com/KB/WCF/WCFWPFChat.aspx" rel="nofollow noreferrer">http://www.codeproject.com/KB/WCF/WCFWPFChat.aspx</a>
  this tutorial use netTcpBinding and endpoint localhost</p>
  
  <p>I change the endpoint localhost to a name based url, forward a port in my router to my development PC, open the same port at Windows firewall. </p>
  
  <p>The client program can chat with each cients program in different machines, BUT the callback connection will lost after one minute.</p>
  
  <p>I also tried changing the binding to wsDualHttpBinding, the clients program can chat with each clients in the same machine and kept the callback connection in the reliableSession inactivityTimeout setting. However another client program in another machine cannot join the server, if I turn off Windows firewall on that machine, the client program can connect.</p>
  
  <p>It seems that tcp binding can let the client program connecting to the server with Windows firewall turn on. but callback connection lost.</p>
  
  <p>and the wsDualHttpBinding can keep the callback connections. but cannot connect to server if Windows firewall on.</p>
  
  <p>Is there a way to kept the netTcpBinding callback connection as in the wsDualHttpBinding?</p>