Paper 2003/093 Original: eprint.iacr.org/2003/093 ↗

Simple Stateless Steganography

Abstract

We put forward the first secret-key steganographic construction that is both black-box (i.e., the sender need not have knowledge of the channel beyond the ability to sample from it) and stateless (i.e., the sender and the recipient need not maintain synchronized state when sending multiple bits). Both of these properties are important: the first because in many settings it is unrealistic to assume detailed knowledge of the underlying channel distribution, and the second because maintaining synchronized state between the sender and the recipient is particularly problematic in steganography, where communication to resynchronize will alert the adversary. For channels of sufficient entropy, our construction is more efficient than previous black-box constructions. Moreover, it is the first one to provide a tradeoff between the number of samples the encoder needs and the rate at which hiddentext is transmitted.