Multiplayer Online Games over Scale-Free Networks: a Viable Solution?

In this paper we discuss the viability of deploying Multi-player Online Games (MOGs) over scale-free networks. We employ a general peer-to-peer overlay network; nodes have a number of neighbors which follows a power law distribution, p_k ∼ k^α , the usual degree distribution that characterizes scale-free nets. Game events generated by nodes during the game evolution are disseminated through the network, based on some (push) gossip protocols run over the created overlay. We experiment with different gossip protocols. Results demonstrate that the employed gossip protocol may greatly influence the ability of disseminating the game data through the scale-free network. In particular, when gossip is performed using a small dissemination probability, a non-negligible percentage of the network is not able to receive the message. This implies that not all players might be able to perceive the game event. Hence, parameters of gossip protocols must be properly tuned to guarantee a full network coverage. Concurrently, it is shown that, due to their low diameter, the use of scale-free networks allows to disseminate game events in very few steps. This could ensure a high level of responsiveness on the dissemination of game events, which is the main objective to pursue when dealing with MOGs.