Any tutorial for client-server system for an MMO?

Hello!

Is there any tutorials or advices about designing a client-server architecture for an MMO game with UE4 (as a client)?

The key parts are:

  • lot of players (both – in game at all and on a single map at the same time)
  • easy scaling (to run on multiple hardware servers)
  • no instancing – all players are in the same world

What is most interesting to me – should I use UE4 for a server as well, or it’s also possible (with no big issues) to build server different ways/technologies and just talk with clients via UDP (for example)?

Thank you!