  The paper presents Deep Hiding Techniques (DHTs) that define general
techniques that can be applied to every network steganography method to improve
its undetectability and make steganogram extraction harder to perform. We
define five groups of techniques that can make steganogram less susceptible to
detection and extraction. For each of the presented group, examples of the
usage are provided based on existing network steganography methods. To authors'
best knowledge presented approach is the first attempt in the state of the art
to systematically describe general solutions that can make steganographic
communication more hidden and steganogram extraction harder to perform.
