In response to negative feedback regarding the upcoming SimCity reboot's always-on DRM, Maxis senior vice president Lucy Bradshaw has stated that the game "was designed to be connected from the ground up," and that the simulation requires access to EA's servers in order to properly handle all computing information, according to a post from Bradshaw on the SimCity website.
Setting certain simulation aspects and rendering on EA's SimCity servers is a technical requirement for the game to run. Data for actions like trading between cities and cross-regional affects (like pollution and fluctuating availability of resources) is processed on EA's servers then returned to players' PCs.
"GlassBox is the engine that drives the entire game-the buildings, the economics, trading, and also the overall simulation that can track data for up to 100,000 individual Sims inside each city," she wrote. "There is a massive amount of computing that goes into all of this, and GlassBox works by attributing portions of the computing to EA servers (the cloud) and some on the player's local computer."
According to Bradshaw, having all players online all the time allows Maxis to collect the information it needs to create and issue weekly local and global challenges for players, as well as keep leaderboards up to date.