How to retain one million simultaneous TCP connections?

Question

I am to design a server that needs to serve millions of clients that are simultaneously connected with the server via TCP.

The data traffic between the server a

Answer 1

I've come across the APE Project a while back. It seems like a dream come true. They can support up to 100k concurrent clients on a single node. Spread them across 10 or 20 nodes, and you can serve millions. Perfect for RESTful applications. Might want to look deeper for any shared namespace. One drawback is that this is a standalone server, as in supplementary to a web server. This server is of course Open Source, so any cost is hardware/ISP related.