title: Testing UDP on localhost
body: <p>I'm currently trying to make an online video game, which currently uses TCP to send packets. I want to use UDP, but I'm extremely new to UDP and I'm having some issues. </p>
  
  <p>When I test my server/client(s) on the same computer (localhost), the packets seem to be interfering with each other.</p>
  
  <p>For example, if the client sends a packet to the server (UDP, 127.0.0.1:1338), the client ends up receiving the packet, since the client is also listening for packets from 127.0.0.1 on port 1338. Similarly, when I try to test 2 clients and 1 server, the clients may send out packets which are meant for the server, but are picked up by the other client.</p>
  
  <p>How can I test UDP on localhost since all packets are being received from/sent to 127.0.0.1:1338? Do I need to implement some sort of layer in my packets that distinguishes if the packet is meant for the server, or a specific client?</p>