How would you verify this system doesn't get abused then? I could easily setup a server, make someone join it and then ban that player. (I agree with HimbeersaftLP, but I'm asking for curiousity)
I will do the plugin part if someone thats good with HTML will do the web part, I can store the raw image data in MySQL and it can be parsed to display just the skins head like on the site @Pitstopers gave.
Ideas: Look for loopholes. They don't pay me to look for loopholes. (Well, they don't pay me at all xD) I'm just the idea person.
You just reminded me that it would be great if you can authenticate the server as one on a voting site and you need many votes to be able to join. The auth flow will be kind of complicated though.
i prefer just a network banlist by creating a global banlist, you would need to get into the a lot more complex problems, like what qualifies as a "bad player" that should be banned globally? most server have subjective rules, unlike defining spam anything that seem automated and adds no value to the conversation other then advertising can be submitted server rules on the other hand, can be hard it would work if run privately as an alliance program to ban players off servers for more severe cases like discourage usage of hacking since now you get banned not just here but every server
I don't think this could be a legitimate system, what if a server has a "bad" admin that decides to ban all the players that kill them in SG or Factions or whatever.
If you store the source of the ban, you can delete all bans from a certain server easily. Moreover, you have to be banned from several servers to be banned on other servers. For example, each server has "reputation index" (most likely correlated with the votes). The ban from each server is multiplied by its reputation index. When another server queries the ban of a player, it retrieves the sum of the reputation index of servers banning that player, and if it exceeds a threshold defined by that server locally, the player is banned.
the most obvious one would be abusing the banning and inflating the banned from server count if it's a public service
or i can tell all my staff members to inflate it, or tell my server followers to inflate it, even tho i dont expect the second option to went well it is still possible