Computer ID worked much like the client's key. It just assigns a relatively unique value to each client that identifies them by the computer they're using. This is mostly used for banning troublemakers and to keep track of which computer they're using so even if they change keys or IP addresses, it'll still know who they are and keep them out.
client/New() if(src.computer_id in banned_ids) del(src)
Are you asking how to prevent multi-keying with computer_id?
Keep track of all the computer_ids that are logged in, and if their computer_id matches an existing computer_id when they attempt to log in, don't let them log in.
var/list/computer_ids = list()
client/New() if(computer_ids.Find(src.computer_id)) src << "Only one player per computer is allowed on this server." del(src) ..() computer_ids += src.computer_id
I am not sure but from where does BYOND get/generate computer_id?
Will the ID remain same if I reinstall BYOND?
Will the ID remain same if I format the PC and install a new Windows?
The Code posted above.
That is supposed to work.
I do not really get what you mean by Acc, I am assuming it account, but still I do not know what Hosting has to do with that piece of code.
1.Create a list of ids.
2.When New Client is called check if the id is there in the list.if there terminate the client else allow the client and add the computer_id to the list.
3.When the Client commits a suicide remove the id from the list.
I am not sure but from where does BYOND get/generate computer_id?
It's based on a variety of information, the exact variety isn't public knowledge.
Will the ID remain same if I reinstall BYOND?
Yes.
Will the ID remain same if I format the PC and install a new Windows?
It might change if you install a new version of Windows, but I don't think so. I know it doesn't change if you format and reinstall the same version of Windows.