title: WCF: Does Close() really close connection?
body: <p>We have some issues with WCF services and I am doing some tests:
  I just created new WCF client and service with <strong>default settings</strong> and monitoring how it works on TCP level. I use .net 4.0 and <strong>net.tcp</strong> binding</p>
  
  <p>And what I see: after <em>using</em> statement closes WCF does not really close connection to server... 
  On TCP level it should send [FIN] package to server, but instead it do nothing, just waiting and <strong>in 2 minutes server terminate connection</strong> with [RST] package. I attached some screenshots from wireshark</p>
  
  <p>I believe it's how wcf works, but I was not able to find some information to confirm it. 
  Also I noticed than if after closing using statement, I open new using statement it use the same port to communicate on client side... (portsharing is false on client) </p>
  
  <p>My questions: </p>
  
  <ul>
  <li>Why WCF does not close connection to server after using statement is
  closed?</li>
  <li>What can I do to make it close connection properly (send [FIN] statement)?</li>
  </ul>
  
  <p>Thanks.
  p.s. I am not attaching any configs, because it's default values which VS2010 creates for me.</p>
  
  <p><img src="https://i.stack.imgur.com/C4UCv.png" alt="wcf communication on tcp level"></p>