Covert Channels

The concept of covertly passing data over a communications channel has existed for hundreds of years. The advent of interconnected computer networks employing intricate layers of protocols created a new medium through which to covertly pass data. This paper explores covert channels on computer networks and examines current and possible future threats. It assesses the risks to individuals and enterprises, and proposes countermeasures to help detect and mitigate the risks brought on by these covert channels.