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. The paper proposes a game-independent, network-based 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 it slightly increases the average response time for players with shorter network delay to the game server.