So Sorunome, did you understand what Kerm was saying? I think I did, but im not sure.
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Yeah, it is kinda de-zentrilizing what the server does.
But we'd some kind of hash algorythm for the calc then to hash all the positions etc

all calcs calculate their hashes and send them to the server (resulting in less data been transmitted).
The server also calcs the position and hashes 'em the same way, it compares all the hashes of the calcs with it own hash.
If they vary the calc either miss-calculated or somebody cheated, so that way the server can send the real positions to the calc etc

you'll just create a string with like "x,y,type,next unit" etc and you'll hash that string.

You know what a hash is?

yes, it can also be used for verification if two large pieces of data are the same - you send 'em through the hash algorythm (if they are the same the hashes will look the same, otherwise VERY likley different). That hash is far shorter than the actual data and thus reduces, let's say, bandwidth

just keep in mind that if the hashes aren't verified correctly the server will still have to send the calc all the positions

Nope the hash is just for integrity check.

-Calc sends hash to server
-Server checks hash
-Hash correct, do nothing
-Hash invalid resend all data to the calc

the thing about the hash is that it is often smaller than the data you originally wanted to send