Sync-MS: Synchronized Messaging Service for Real-Time Multi-Player Distributed Games

Real-time, online multi-player games are becoming increasingly popular due to advances in game design and the proliferation of broadband Internet access. However, fairness remains a major challenge when players over large geographic areas participate in a client-server based game together. This paper proposes a game-independent, networkbased service, called Sync-MS, that balances the trade-off between response time and fairness. Sync-MS uses two mechanisms, Sync-out and Sync-in, to address state update fairness and player action fairness, respectively. Two metrics, ahead and behind measured against the fair order, are defined to evaluate Sync-MS’s fairness performance. Simulation results show that Sync-MS dramatically improves player action fairness for all players while slightly increases average response time for players with shorter network delay to the game server.