DATA SECURITY
Steganography is the art and science of communication in such a way that the presence of any messages can not be tracked. It may be associated with field of hiding information which has received considerable attention in recent times. One may differentiate two general directions in information hiding which is determined by the power of an adversary and protection against only the detection of a message by passive adversary and hiding a message such that can never be removed by an any active adversary .So information theoretic model for steganography with passive adversary is proposed. The adversarys task of distinguishing between an innocent cover message C & the modified message S containing hidden information is interpreted as a hypothesis testing problem.
