[gilgoomesh]

Except there's no assumption here that the 1 million connections are between just two computers. Clients are spread over 50 different EC2 instances (which each have a unique address). The host does not need more ports in this scenario and the clients are using 20,000 ports (possible without altering port allocation).

[Erwin]

This was a reply to tmartiro's thread, where he says "You can also open 1 million connections using one linux box" and describes how you could do it a single instance rather than 50 separate ones; adlpz asked "what would be the point of that".