Oh, screw it. Let's just have a setup like EVE:
A unique aspect of EVE is that it is run on one server. In EVE you can find over 10,000 players at any given time interacting in the same persistent universe. Other MMORPGS are played on multiple servers called Shards; these have a limited number of players on each, usually between 500 and 3000.
There is a centralized server cluster, located in London, with several proprietary proxy (slave) servers. The proxy servers have dedicated bandwidth to the central cluster. The proxy servers take some of the load off the game logic servers in the cluster by doing data integrity checks and virtual multicasting, making them – in a sense – a software router.
This server architecture, together with clever game design, allows us to have more players, distributed over greater geographical distances, together in the same world, breaking records held by our predecessors in the MMOG genre.