A novel distributed covert channel in HTTP
Fei Wang, Liusheng Huang, Haibo Miao, Miaomiao Tian · Security and Communication Networks · 2013
ABSTRACT In this paper, we propose a novel distributed covert channel in HTTP. Different from traditional covert channels in HTTP, the channel deploys multiple HTTP clients to dilute steganographic features. In a proper multiple‐to‐multiple transmission model based on the modulation of URLs, the channel is efficient and reliable. With a Poisson request generator, simulating behaviors of normal HTTP visitors, the covert traffic has a legitimate HTTP appearance that helps it be undetectable. The transmission experiments prove that the channel is error free and has a high transmission rate. The results of the undetectability experiment show that the channel is adjustable. By adjusting a certain parameter, the channel can trade off two different features, the transmission rate and the undetectability, which can meet different demands in practical applications. Copyright © 2013 John Wiley & Sons, Ltd.