Steganography in games: A general methodology and its application to the game of Go

Techniques to hide valuable information within seemingly harmless messages have been widely used for centuries. Typically, their use is appropriate when encryption is not available or not adequate (e.g. when available cryptography is too weak), or simply when it is convenient that no external observer can infer that some information is being exchanged. In the digital era, new cover mediums for hiding data in communication are constantly being proposed, from the classical image files (such as bmp, gif, and jpg formats) to audio files (i.e. wav and mp3), text and html documents, emails disguised as spam, TCP/IP packets, executables programs, DNA strands, etc. In this work, we present and analyze a novel methodology that illustrates how games (such as Chess, Backgammon, Go, etc.) can be used to hide digital contents. We also look at some of its possible advantages and limitations when compared with other techniques, discussing some improvements and extensions. Finally, we present the results of a first implementation of an open-source prototype, called StegoGo, for hiding digital contents in Go games.