Cheating Prevention in Multiplayer Online Games

Cheating Prevention in Multiplayer Online Games Shane Willcox Introduction One of the many modes within most games these days is playing with other players with Online Multiplayer. While most games have a multiplayer mode, some games are based and built for multiplayer. Multiplayer games are become extremely popular with millions of people playing them every day. Since Multiplayer games attract many players, there are always those people who go out of their way to find ways to cheat to gain advantages over others and sometimes ruin other player’s experiences playing against or with a cheater. Cheating in games have almost always been there right from the start, however cheats were single player only which is normally over looked as they only affect the game and the cheater and no one else, however with the evolution of gaming and multiplayer, cheating has spread to this type of gaming. Types of Cheating It can cost a company thousands to try and stop players that are using cheating methods by detecting and preventing them. (Yampolskiy(2008)). With Online multiplayer games there are many different types of cheats can be used if a game is not detecting and preventing cheats and can heavily damage the game and can receive complaints from the game’s community, some classes of cheats include: Reflex Augmentation which is using artificially intelligent (AI) computer assistant tools in order to perform actions that are faster than should be and also provides unfair precision humans could not possibly perform. For example the use of an aim-bot that can be used on some FPS’s (First Person Shooter) and aim-bots provide unfair precision on opponents giving the opponents no chance to react (Yampolskiy(2008)). Another is Authoritative Clients Utilizing meaning the hacking to altered commands (Yampolskiy(2008)). Information Exposure which getting access to hidden information. (Yampolskiy(2008)). On Example is a wall-hack which lets the cheat see through walls. Compromised Servers, which is the changing of game states at a server level. For Example using artificial lag (Yampolskiy(2008)). Exploits due to poor game design or overlooked features to take an unfair advantage within a certain game. For example in some Call of Duty games there are some map glitches which allows players to access parts of a multiplayer map that should not be able to be accessed, as well as game ruining glitches such as in Call of Duty Modern Warfare 2, there is an exploit that allowed players to get an unlimited amount of explosives that ruined most of the player’s experiences with explosives being insanely overpowered and unfair. Unfortunately there is a lot of cheating methods within the online community of games and some can impact players causing complains from fans and if the fans are reacting negatively that will undoubtable affect the game’s sales and cause the certain games to become unpopulated within the game’s servers as well as if the developers can fix and pervert the cheaters then the damage has already been done. One genre that can be affected by cheaters is FPSs. There reason for this is that FPS’s are some of the most popular games to be played online and their design can lead to cheats coming up with cheats that can gain advantage. One called a ‘wall-hack’ that lets the cheaters see enemies through game objects that should not be able to be seen through and therefore get can extreme advantage. However an aimbot is much more unfair. Aimbot and there Preventions An aimbot or aiming robot is essentially a type of tool that lets the user automatically lock on to the enemy players. This is done by having the aimbot gain prohibitive access to the internals of the game and gives the user the ability to acquire enemy targets instantly when the target is in a direct sight line (Yu(2012)) and sometimes even not user’s viewpoint even if game objects such as buildings and walls are in the game lets the players shoot through them, for example in the Call Of Duty or Battlefield series. This lets users to defeat targets with both speed and pinpoint accuracy even if the target is moving at high speed and human players are probably incapable of achieving this all the time, even if the player is extremely skilled with a game it is almost impossible. One method that could be used to detect aimbot behaviour is by having a Dynamic Bayesian network (DBN) model incorporated into the game’s system. The DBN shows different kinds of variables that can determine whether a player is a cheater and shows that they have detected them. Some variables that can be looked at is if the player is moving, if the target is moving, if the aiming direction of the player has changed, and the distance between the player and the aiming target. (Yeung (2006)). Using this model is known as a ‘first order Markov process’, which is the making of prediction from information from the present state. The process is implemented because aiming is a process which is heavily dependent on what is happening in real time since when a player aimed adjustments are needed to keep accuracy on point such as control of recoil (if any) and rate of fire(Yeung(2006)). So if the game using the DBN sees there is pattern from a player and there is enough evidence that a certain player is using an aim bot with the variables supported, then the game can detect that the player is indeed a cheater (Yeung (2006)). Also data could be inputted into the game to tell the game to compared the accuracy of a player that is highly skilled with the game and have that as a comparison to use on players and if there is a player that is exceed the accuracy every time then they could also be detected. Lag-Switches and there prevention Common cheats normally happen on a gaming level due to the design of the game and cheats that can affect the actual gameplay and not the network latency of players. However cheaters have found a way to affect the latency for players and gain an unfair advantage. Firstly however network latency is the delay that players have when there is a communication of data over a server or network. This happens with any type of online game as the data from the entered commands that the players input is sent to the server of the game and then has the action happen. However cheaters have found ways to cheat over a network. A lag switchis a smallEthernetdevice that is installed to ahome networkand is connected between the gaming device and the homenetwork routerwhich enables the user to insert delays to the flow of traffic which is local to the Internet and is not related to the network switches that are normal. Activing a lag switch makes device run on a set timer and this blocks all traffic between the gaming device and the Internet within that period which causes artificial lag. So when the user has the lag switch in action, to others they look as if they are either frozen in place however the user moves freely and can freely kill the enemy player. Some points of view of a lag switcher are that they moving normally and in fact the opposing team are frozen in place when in their line of site. When the timer stops, the gaming device will re-synchronize with theonline game. However for a user to use lag switch they must be the host of the game on a host based server that most games had or still have and if the user is using a lag switch in a team based mode, then the lag switchers team is normally unaffected by the artificial lag(Bradley(n./a)). Lag Switches can be found on many online games or modes, such as Counter Strike, Call of Duty, MOBA’s (Multiplayer Online Battle Arena’s) and many more. Since network cheating is sometimes much harder to fix than other common cheats, there sometimes more expensive ways to combat network cheats such. Ways that game developers can stop the usage of lag switching is to use a DBN model again to maybe check if the players have common lag spikes however there can be a problem because if the game is are banning all the players with lag strikes, then some players might just have poor internet and get banned for no reason. So one of the best implementations to combat lag switchers and lag based cheats, is to use dedicated servers. Dedicated servers can be used by game companies to allow players to have a fair networking environment as well as the developers having control of the host mechanisms with each server players are playing on. Dedicated servers are essentially servers that are run by the developers of the game and they basically act as a non-playing player as the players connect a server that has a stable connection and enables high bandwidth instead of players connecting to a host that could have terrible internet quality. Dedicated Servers can stop Lag switchers because a lag switch user normally has to be the host of the game for them to cheat and use the full effects of a lag switch. However dedicated servers can be very expensive to implement depending on the size and popularity of the game. More Cheating Preventions While the above talked about cheat preventions for some popular methods of cheating, there is still some other prevention that should always be looked in to. Developers should have built-in cheating detection systems for everything that could be affected by cheaters. This means that they can detect or find unusual activities, and produce alarms (Chen (2005)). Have a Reporting system within the game, so that if a player encounters a cheater, then the player can report them or maybe have a system in place that lets players kick cheaters during gameplay, however there would need to be another system to see if the player accused of cheating is actually cheating. If there is an exploit is reported, then the developers can put patches in the form of updates to fix the exploits. Conclusion Overall there are a many ways when it comes down to the prevention of cheating within online multiplayer. With there being many types of cheats such as Reflex Augmentation, Information Exposure, Compromised Servers and Exploits, there is cheating preventions that can help stop them. For Example to stop one of the biggest cheats in FPS’s, an aimbot can be prevented by using a DBN model incorporated into the game’s system by having the model look at certain variables of players to determine of their actions are legit and are capable of being done by a Human player. Then the developers can decide what to do with players who have been detected of cheating. While another example of cheating however over a network is lags switch that is a piece of equipment that causes artificial lag to games. The user of a lag switch makes the opposing players lag by either having the user seem like they have frozen or by having the opponents freeze in when they are in direct sight of the user. The most affect combatant against this is the usage of dedicated servers as they are the hosts for servers instead of players and lag switchers need to be the host of a game in order for them to take advantage of a lag switch. When you compare the methods of using prevention on network cheating and game cheating, they are both very different because of each having different factors that the developers have to take into consideration, however they both can work to together to overcome the goal of prevention. This because with dedicated servers, since you can have the developers monitor the servers since the developers have full control of the host of each server and this gets rid of lag switches. References Yampolskiy, R.V. Yampolskiy, R.V. 2008, Detecting and Controlling Cheating in Online Poker, IEEE CCP, , pp. 848. Yu, S., Hammerla, N., Yan, J. Andras, P. 2012, A statistical aimbot detection method for online FPS games, IEEE, , pp. 1. Yeung, S.F., Lui, J.C.S., Liu, J. Yan, J. 2006, Detecting cheaters for multiplayer games: theory, design and implementation, , pp. 1178 Bradley, M., N/A, â€Å"What Is A Lag Switch?† http://compnetworking.about.com/od/consumerelectronicsnetworks/f/lag_switches.htm Chen, Y., Hwang, J., Song, R., Yee, G. Korba, L. 2005, Online gaming cheating and security issue, , pp. 518.