Steganography: Now that you have seen one of the uses of the Steganography let’s go further and see another possible use of Steganography in cryptographic applications.
Imagine you are in an insecure channel and your entire communication can traced using different methods to be more precise I describe a condition that sometimes happens for the programmer who wants to have their programs license kept safe! So that you make an internet connection between your designed program for checking the validity of license, but the cracker who tries to crack you software, can trace all communication between your software and the server, and he is aware of what is being transacted between your software and the server and once he can recover the message from your server indicating that the license is correct and activates your software! So that he makes a patch which generates the same packet virtually. So that by tracing the communication between the server and the software he could succeed! There are two solutions to stop him doing so. The first one is use of a public key between software and the server, which also vulnerable in this particular situation. But the other one is to hide the activation key somewhere between the update packets so that if the attacker wants to update the software, he gets the wrong activation key, and your software expires and also you can trace the cracker, and by copy right rules you can sue against him/her.
The use of Steganography is also very useful in military applications. During the cold war there were some magazines which contained steganographic data inside their content so that the spies in the other side could get the command and information through public unsafe channels such as magazines and news papers.
Also it is said that the terrorists used Steganography to communicate for hiding their conversations in the September 11 attacks. So that after September 11 Steganography got more attention and several methods were proposed for recovering any possible Steganographic data.
The act of analyzing information for recovering steganographic information from the data is called Steganalysis. There have been many papers published on the Steganalysis (for example: Blind Image Steganalysis Based on Statistical Analysis of Empirical Matrix- by Chen et al in IEEE proceeding- (ICPR’06))