Well this gets complex and I haven't fully researched enough yet but I will try and decribe what I understand so far and the premise that I'm working off of.

My model for my massively multiplayer project is that the server will run the levels or zones and the client must be updated as to any activity in that zone. The client is essentially a renderer that pushes user activity requests to the server who makes the coresponding action and sends the appropriate reponse to the client.

Example: Client presses hotkey '2' to activate the spell in the second slot of his spellbar. The Client sends a message to the server that he wants to activate hotkey '2'. The server checks the client's record for what action is currently assigned to hotkey 2 and executes the instruction and then sends the information to all applicable clients in the zone that clientxx is casting spell#2 so they can make the appropriate 3D rendering.

My understanding of what is needed in the DLL is a protocol written to allow the client and server to pass information between each other in an extremely fast and efficient manner. Multiple levels of priority will be needed depending on the nature of the instruction that is waiting to be sent and in the case of my network design the protocol must be able to speak to multiple servers simultaneously. (example: I am currently wanting to run game chat through it's own server entirely, so all chat related activitity will be sent to a different server than the player activity.)

Does my understanding of what the DLL will do sound at all correct?

I apologize for my lack of understanding but I'm doing the best I can with a fairly exhausted brain =)

Thanks for your input I really appreciate the help.

-edit- In answer to your question I don't have any experience with the SDK as I havent purchased it yet. I will do so this week I think unless A6 has other ways of implementing external proggies?

Mark