basically I have a game client that has communicate with a server for almost every action it takes, the game is in Java (using LWJGL) and right now I will start making the server.

The base of the game is normally one client communicating with the server alone, but I will require later on for several clients to work together for some functionalities.

I've already read how authentication server should be sepparated and I intend on doing it. The problem is I am completely inexperienced in this kind of server-side programming, all I've ever programmed were JSF web applications.

I imagine I'll do socket connections for pretty much every game communication since HTML is very slow, but I still don't really know where to start on my server.

I would appreciate reading material or guidelines on where to start, what architecture should the game server have and maybe some suggestions on frameworks that could help me getting the client-server communication.

I've looked into JNAG but I have no experience with this kind of thing, so I can't really tell if it is a solid and good messaging layer.

Any help is appreciated... Thanks !

EDIT:

Just a little more information about the game. It is intended to be a very complex game with several functionalities, making some functionalities a "program" inside the program. It is not an usual game, like FPS or RPG but I intend on having a lot of users using these many different "programs" inside the game.

If I wasn't clear enough, I'd really appreciate people that have already developed games with java client/server architecture, how they communicated, any frameworks, apis, messaging systems, etc.

It is not a question of lack of knowledge of language, more a question for advice, so I don't end up creating something that works, but in the later stages will have to be rewriten for any kind of limiting reason. PS: sorry if my english is not perfect...