i think there should be accounts to play
1. register forums for posting/playing(?)
2. you CAN'T(?) log into another account, you make one, create characters in that account, thats all, you cant log into another account, because your first one is bounded (can be deleted by GM by request if any glitch occur to make another account(?))
3. character limit for one account should be 4 chars, and to log into another you need to log off first char and wait 20 seconds (prevents dual logging, and doesnt slow game)
4. heres the anti-dual log idea, im not any kind of coder, i just believe i got basic knowledge... so there should be a very little size cache file registering your account/chars. it is saved in server with account's name, there should be no password stored, only data telling is someone online and in what char, if both chars are on, ban, if two accounts (though not possible if bounded?) are used by same ip, ban. (unless theres seriously good exceptional reason).
4.1. optional, but i think itll be more useful to have that cache file stored in private computer too, so it has to be identical as in server's. dunno why, but i feel that making it more secure.
5. i know i didnt make much sense because im a noob.