Gave the "time-stamp" part some additional thinking.
> "constantly uploading map cache"
Was actually only thinking about mmaps that are send by the auto-mapping process.
Assuming those mmaps are only send (client to mapper-server) when a new/updated mmap is received (by client from game server).The map-export feature poses a problem here. As in what 'mmap time-stamp' to use. Using the 'client to mapping server' upload time would not work. (
as in: will be abused at a heavy cost (processing power) of the mapping server)
I kinda figured mmaps that are send by the auto-mapping are somewhat resistant to time manipulation/(abuse). Mainly because that time would/should be the current time.
But with open source code its a given that is not true. Which kinda undermines the whole '
how old was the last mmap update' process.
Recap: Crucial key part behind the 'whole idea' is the mmap time-stamp. As such it would need to have a high trust/secure level. But as usual with security issues: its tricky and in this case probably not really solvable.
Ergo: putting idea on ice.
(+ You got plenty of other stuff on your wish list already.

)