title: Simulate multiple IP addresses for testing
body: <p>I need to simulate multiple embedded server devices that are typically used for motor control.  In real life, there can be multiple servers on the network and our desktop software acts as a client to all the motor servers simultaneously.  We have a half-dozen of these motor control servers on hand for basic testing, but it's getting expensive to test bigger systems with the real hardware.  I'd like to build a simulator that can look like many servers on the network to test our client software.</p>
  
  <p>How can I build a simulator that will look like it has many IP addresses on the same port without physically having many NIC's.  For example, the client software will try to connect to servers 192.168.10.1 thru 192.168.10.50 on port 1111.  The simulator will accept all of those connections and run simulations as if it were moving physical motors and send back simulated data on those socket connections.</p>
  
  <p>Can I use a router to map all of those addresses to a single testing server, or ideally, is there a way to use localhost to 'spoof' those IP addresses?  The client software is written in .Net, but Python ideas would be welcomed as well.</p>