Consider the implementation strategies for massively multiplayer online games. In particular, what advantages do you see in adopting a single server approach for representing the state of the multiplayer game? What problems can you identify and how might they be resolved?

What will be an ideal response?

The advantages of having a single server maintain a representation of the game are that:
(1) there is a single copy and hence no need to maintain consistency of multiple copies; and
(2) clients have a single place to go to discover this state. There may also be advantages to having a global view of the entire systems state.
The potential problems are that this single server may fail and may also become a bottleneck affecting the performance and scalability of the approach. To handle failure, it would be necessary to introduce replication, which in turn would require a solution to maintaining consistency across replicas. There are a number of solutions to improving performance and scalability including running the server on a cluster architecture, or again using replication and load balancing within the distributed environment. Alternatively, a peer-to-peer solution can be adopted. These techniques are covered throughout the book.