Network based intrusion detection to detect steganographic communication channels - on the example of images

Today we find a wide variety of intrusion detection systems (IDS). They can detect attacks against network services or certain hosts. These attacks often violate integrity, availability and confidentiality of a IT-system or its data. One attack against data is the loss of confidentiality. With the help of steganographic tools one can hide data in a cover media and transmit it over the network. At this time nowadays no intrusion detection system is available to detect this security violation. In this paper we discuss the design of an IDS that is able to detect steganographic communication in image data. Future intrusion response systems (IRS) could be trigged by the IDS to react in accordance to the policy.