The partial migration of game state and dynamic server selection to reduce latency

Abstract

Massively multi-player online games (MMOGs) have stringent latency requirements and must support large numbers of concurrent players. To handle these conflicting requirements, it is common to divide the virtual environment into virtual regions. As MMOGs are world-spanning games, it is plausible to disperse these regions on geographically distributed servers. Core selection can then be applied to locate an optimal server for placing a region, based on player latencies. Functionality for migrating objects supports this objective, with a distributed name server ensuring that references to the moved objects are maintained. As a result we anticipate a decrease in the aggregate latency for the affected players. The core selection relies on a set of servers and measurements of the interacting players latencies. Measuring these latencies by actively probing the network is not scalable for a large number of players. We therefore explore the use of latency estimation techniques to gather this information.