  The paper presents StegBlocks, which defines a new concept for performing
undetectable hidden communication. StegBlocks is a general approach for
constructing methods of network steganography. In StegBlocks, one has to
determine objects with defined properties which will be used to transfer hidden
messages. The objects are dependent on a specific network protocol (or
application) used as a carrier for a given network steganography method.
Moreover, the paper presents the approach to perfect undetectability of network
steganography, which was developed based on the rules of undetectability for
general steganography. The approach to undetectability of network steganography
was used to show the possibility of developing perfectly undetectable network
steganography methods using the StegBlocks concept.
