Toward network steganography detection

Network steganography is a recently introduced, general term which describes all information hiding methods that may be used to hide secret data in the normal data transmissions of users. While sending encrypted information, enabled by some cryptographic algorithm, protects messages from being captured by unauthorized parties, steganographic techniques enable concealing the fact that a message is being sent, and if not detected, make the sender and receiver “invisible”. Network steganography methods may be viewed as a threat to network security, as they may be used as a tool for confidential information leakage, for example. For this reason, it is important to identify possibilities for covert communication, as knowledge of information hiding procedures may be used to develop countermeasures. To detect existence of hidden data inside the network traffic steganalysis methods are used. Steganalysis tools identify suspected network communication and try to determine whether or not it carries hidden information. If it is possible they should also recover hidden information Steganographic techniques arise and evolve with the development of network protocols and mechanisms, and are expected to be used in secret communication or information sharing. Now, it becomes a hot topic due to the wide spread of information networks, e.g., multimedia services in networks and social networks.