A Hybrid P2P System to Support MMORPG Playability

MMORPG (Massively Multiplayer Online Role Player Games) is the most popular genre among network gamers, and now attract millions of users, who play in an evolving virtual world simultaneously. This huge amount of concurrent players requires the availability of high performance computation servers to provide QoS. Additionally, gaming aware distribution mechanisms are needed to distribute game instances among servers avoiding load unbalances that affect performance negatively. In this work, we tackle the problem of system scalability by means of a hybrid P2P architecture. To distribute game instances of MMORPG over the peers of this architecture, we propose two mapping mechanisms. The Direct Mapping distributes players on demand in order to minimize waiting times. The Group Mapping groups players on queues of different sizes before distributing them, in order to better exploit peers capabilities. The effectiveness and differences in terms of latency, waiting time and reliability of both mapping mechanisms are evaluated through simulation. We show that Group Mapping provides lower latency response, while Direct Mapping distributes game instances faster. In relation to reliability, our results show that the Direct Mapping policy achieves a failure probability under 7% in the worst cases.