title: How do I increase the priority of a TCP packet in Delphi?
body: <p>I have a server application that receives some special TCP packet from a client and needs to react to it as soon as possible by sending an high-level ACK to the client (the TCP ACK won't suite my needs).</p>
  
  <p>However, this server is really network intensive and sometimes the packet will take too long to be sent (like 200ms in a local network, when a simple server application can send it in less than 1ms).</p>
  
  <p>Is there a way to mark this packet with a high-priority tag or something like that in Delphi? Or maybe with the Win32 API?</p>
  
  <p>Thanks in advance.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Thanks for all the answers so far. I'll add some details. My product has the following setup: there are several devices that are built upon vehicles with WIFI conectivity. When they arrive at the garage, those device connect to my server and start to transmit data. </p>
  
  <p>Because of hardware limitations, I implemented a high-level ACK to make the device aware that the last packet arrived successfully (please, don't argue about this - the data may be broken even if I got a correct TCP ACK). However, if I use my server software, that communicates with a remote database, to issue this ACK, I get very long delay (>200ms). If I use an exclusive software to do this task, I get small latencies (&lt;1ms). So, I was imagining if I could just tell Windows to send those special packets first, as it <strong>seems</strong> to me that this package is getting delayed so the database ones can get delivered.</p>
  
  <p>That's the motivation behind my question.</p>
  
  <p><strong>EDIT 2</strong></p>
  
  <p>As requested: this is legacy software and I'm using the legacy <em>dclsockets140.bpl</em> package and <em>Delphi 2010 (14.0.3593.25826)</em>.</p>