You can have all peers communicate with a central "hive" Even if you are running multiple instances of the game 100 rooms with 10 players each... you can still send info to
A hive that would be an external database
Lets say
mysql
and players would send info to a php file which would interact with database
Getting and writing data is easy enough - couple tutorials already using mysql and php.
Couple of unknowns exist, you obviously can't write ever tick, or even every second unless you have a monster database server, or bridged (is that correct term?), but you will bottleneck...Because you will be limited by concurrent connections.
So when to pass the data on???? And what are the consequences? Lag, game freeze, etc
A single high scoreshould be fairly easy to do... (tongue in cheek, nothing is easy - lol)
I've been experimenting, not successfully with a multiplayer save feature... "I'm talking about trying to save players game whilst using the multiplayer plugin"
So it stores users login credentials and game progress in webstorage (fair enough), but I've been trying to store it in a "hive" an external server.
The idea is to have a login system that logs user into multiplayer game, but also logs them into hive, and then loads their game progress.
Why? Why not, I'm thinking along the lines of boardgames, card games, something where I can play a game with my family over the weekend, and next sunday it is all still there where "we" left off.
Of course, time restraints and everything takes a bit of a back seat.
But running multiplayer games. Limited to max users. or even independant single player games -no problem for highscore.