Research And Design Of Novel Network Covert Timing Channels

With the rapid development of network communication technology,the transmis-sion speed of network equipment has been continuously improved,and Internet applica-tions have been increasingly popular which makes the information transmission more and more convenient and efficient.At the same time,information security problems frequently occur and privacy leakage problems are ubiquitous.Therefore,the security of information transmission has become a major concern in the information age.With the improvement of the attackers' cipher deciphering ability,traditional data encryption technology can no longer meet the requirements of the current era.Therefore,informa-tion hiding technology,as an emerging technology,embeds hidden information into some carriers without obvious influence,so as to prevent attackers from discovering the existence of secret information.As a dynamic information hiding technology,net-work covert channels have attracted wide attention of researchers and become a hot spot in the field of information hiding.In recent years,covert channel detection technology has been developing continuously.Many network covert channels are lack of strong undetectability and robustness,and are faced with the risk of being discovered by at-tackers.As a result,they can no longer guarantee the covertness,security and reliability of communication.For the current research status,this paper takes network flow as the carrier to carry out research on covert timing channels.The main work is as follows:1.By combining the first-order,second-order and higher-order statistical charac-teristics of distribution,this paper analyze the packet interval distribution characteristics from five perspectives,and then analyze the factors affecting the undetectability per-formance and robustness.2.Based on the characteristics of legitimate network flows and the corresponding detection methods,this paper designed a novel network covert channel to ensure strong undetectability and good robustness in face of network packet loss,delay and jitter.3.For the practicability of network covert timing channel,this paper proposed a practical system framework and the functional design of each module.With the devel-opment of detection technology,systematization and modularization helps researchers to develop and improve existing covert channels continuously.