This paper describes the design and implementation of a scheme for hiding information in translated natural language text, and presents experimental results using the implemented system. Unlike the previous work, which required the presence of both the source and the translation, the protocol presented in this paper requires only the translated text for recovering the hidden message. This is a significant improvement, as transmitting the source text was both wasteful of resources and less secure. The security of the system is now improved not only because the source text is no longer available to the adversary, but also because a broader repertoire of defenses (such as mixing human and machine translation) can now be used.
Ryan Stutsman, Christian Grothoff, Mikhail J. Atal