If you''re looking into writing a server capable of handling > 200 clients, you''re going to need to figure out what platform your server will run on. It''s fairly rare to have game servers that support that many clients that run on multiple platforms. The reason is that the optimal server design for one platform is most likely not the same on another platform.

That''s not to say that it can''t be done, just that it adds complexity that will probably be a lot of work unless you''re very strong in C++ inheritance and can come up with a good design for some abstract classes or have some other idea up your sleeve.

The sad state of affairs is that most publishers have it in their heads that every game programming book they publish has to also include all the basics of DirectX. This is an idiotic idea of course, and fills up half the book with stuff you either alredy know, or probably own a better book for.

As for which method to use...

The fact of the matter is, only I/O Completion ports will scale well enough to handle a LARGE number of players on a single server. That being said, 200 players is not very many... you might even get away with giving every player their own socket thread with that many people. But like ekenslow said, that will not scale.