<li>Server sends from the second port on the already-connected IP 
address, s1p2. If received, then the client is using address-restricted cone 
NAT.</li>
  <li>Client sends to another IP address on the server, from its first 
(already connected) port. If the IP address and port is the same, then 
the client uses the same external IP address and port to all connections
 from the same source address. This is port-restricted NAT.</li>
  <li>Else symmetric NAT.</li>
</ol>
<p><span class="RakNetBlueHea