Archive-based Covert Channel in Sensor Streaming Data

Abstract

With the advent of the Internet-of-Things, sensor data streams are widespread and thus a promising target for network steganography including covert channels. Therefore, we present an approach where the covert sender and receiver first build an archive of values that occur in the stream over a time interval, and then encode bits of the secret message via sensor stream values belonging to the class of seen values or not. If a sensor value’s category does not match the required bit value, it is adapted to switch its category. The chosen value minimizes the distance to the original sensor value to improve stealthiness. Furthermore, we present an application scenario and an analysis of the channel’s detectability, in particular how detectability and steganographic bandwidth can be traded against each other. We have tested the approach and the proposed detec-tion metrics via simulation experiments.

Keywords

• Covert channel
• network steganography
• sensor data