On importance of steganographic cost for network steganography

Network steganography encompasses the information hiding techniques that can be applied in communication network environments and that utilize hidden data carriers for this purpose. In this paper, we introduce a characteristic called steganographic cost, which is an indicator for the degradation or distortion of the carrier caused by the application of the steganographic method. Based on exemplary cases for single- and multi-method steganographic cost analyses, we observe that it can be an important characteristic that allows to express hidden data carrier degradation-similarly, Mean-Square Error or Peak Signal-to-Noise Ratio is utilized for digital media steganography. Steganographic cost can moreover be helpful to analyze the relationships between two or more steganographic methods applied to the same hidden data carrier.