Call of Duty 2: Big Red One will utilize DemonWare’s State Engine middleware. Activision has announced that they will use the middleware to provide "seamless, state-of-the-art, 16-player, cross-platform, multiplayer online gaming to players worlwide." That means that PS2 players will be able to compete against Xbox players. DemonWare provides programming that eliminates the need to re-invent netcode for multi-player games.
"By utilizing DemonWare’s middleware, the development team is able to focus on creating great gameplay experiences while knowing that the technical aspects of the multiplayer component are managed," Chuck Huebner, head of Activision’s Worldwide Studios, commented. "When Call of Duty 2: Big Red One ships this fall, sixteen players will be able to engage in explosive Local Area Network (LAN) and Internet multi-player action on their Xbox or PlayStation 2 gaming systems, quickly and seamlessly."