AC/DC: an algorithm for cheating detection by cheating

ABSTRACT

Time cheats represent some of the most crucial issues in online gaming. Since they act on timing properties of generated game events, these malicious schemes are particularly difficult to thwart when distributed games are deployed over peer-to-peer architectures. Indeed, the absence of a global clock shared among peers enables cheaters to see into the future by waiting for events generated by other peers before generating its own ones (lookahead cheat). This may give an unfair advantage to the cheater. We consider a version of lookahead cheat generalized in the context of real-time (i.e., not round-based) games. To face this time cheat, we present AC/DC, an Algorithm for Cheating Detection by Cheating. This algorithm enables to detect cheaters based on monitoring of network latencies. The basic idea is that of conducting against each suspected peer a sort of cheating counterattack, by delaying events before notifying them to the (hypothetic) cheater. This permits to detect whether that peer waits for these events before generating its own ones. Our claim is that an approach based on the monitoring of communication patterns among peers allows cheat detection without affecting the performances of the game.

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INDEX TERMS

Primary Classification:
  K. Computing Milieux
  K.8 PERSONAL COMPUTING
      K.8.0 General
          Subjects: Games

General Terms:
Algorithms, Security

Keywords:
cheating, online games, peer-to-peer, synchronization