Massive multiplayer online games (MMOGs) have stringent latency requirements, and must support a large amount of concurrent players. To handle these conflicting requirements, it is common to divide the virtual world into smaller virtual regions. As MMOGs attract players from all over the world, it is plausible to disperse these regions on geographically distributed servers. Core-node selection algorithms can then be applied to locate an optimal server for placing a region or instance, based on client latencies. In this thesis, we have designed and implemented a prototype of a middleware which supports core-node selection algorithms and migration. Using this middleware, we have built a test application which simulates a simple MMOG. This application has been tested on PlanetLab, with clients and servers distributed all over the world. We have also performed micro benchmarks on the middleware itself, to test how it performs.