Stealth transmission in free space optical communication systems using amplified spontaneous emission noise

One of the challenging real-world problems in the communication network is to secure the communication system that deals with a large data. Perhaps even a more challenging version of this scenario is when the channel that transmits the information is a wireless media. This thesis introduces a steganography technique to secure the physical layer of the communication system. It enhances the benefits by using optical communication rather than radio frequency (RF) communication, especially in terms of transmitting a large scale of data. This thesis demonstrates that we can transmit secure large information in free space (air) using steganography mechanism and free space optical (FSO) channel. In this work, we built a secure optical wireless communication prototype. We analyzed the performance of this system using eye diagram and bit-error rate (BER) measurements. The application of this work can be used in many applications such as monitoring enterprise and campus connectivity, smart sensors and internet of things networks

Dual Rate Control for Security in Cyber-physical Systems

We consider malicious attacks on actuators and sensors of a feedback system which can be modeled as additive, possibly unbounded, disturbances at the digital (cyber) part of the feedback loop. We precisely characterize the role of the unstable poles and zeros of the system in the ability to detect stealthy attacks in the context of the sampled data implementation of the controller in feedback with the continuous (physical) plant. We show that, if there is a single sensor that is guaranteed to be secure and the plant is observable from that sensor, then there exist a class of multirate sampled data controllers that ensure that all attacks remain detectable. These dual rate controllers are sampling the output faster than the zero order hold rate that operates on the control input and as such, they can even provide better nominal performance than single rate, at the price of higher sampling of the continuous output

A Scalable Specification-Agnostic Multi-Sensor Anomaly Detection System for IIoT Environments

Advanced sensing is a key ingredient for intelligent control in Industrial Internet of Things (IIoT) environments. Coupled with enhanced communication capabilities, sensors are becoming increasingly vulnerable to cyberattacks, thereby jeopardizing the often safety-critical underlying cyber-physical system. One prominent approach to sensor-level attack detection in modern industrial environments, named PASAD, has recently been proposed in the literature. PASAD is a process-aware stealthy-attack detection mechanism that has shown promising capabilities in detecting anomalous, potentially malicious behavior through real-time monitoring of sensor measurements. Although fast and lightweight, a major limitation of PASAD is that it is univariate, meaning that only a single sensor can be monitored by one instance of the algorithm. This impediment poses serious concerns on its scalability, especially in modernized industrial environments, which typically employ a plethora of sensors. This paper generalizes PASAD to the multivariate case, where a plurality of sensors can be monitored concurrently with little added complexity. This generalization has the evident advantage of offering scalability potential for deployment in future-focused industrial environments, which are undergoing growing integration between the digital and physical worlds

OnionBots: Subverting Privacy Infrastructure for Cyber Attacks

Over the last decade botnets survived by adopting a sequence of increasingly sophisticated strategies to evade detection and take overs, and to monetize their infrastructure. At the same time, the success of privacy infrastructures such as Tor opened the door to illegal activities, including botnets, ransomware, and a marketplace for drugs and contraband. We contend that the next waves of botnets will extensively subvert privacy infrastructure and cryptographic mechanisms. In this work we propose to preemptively investigate the design and mitigation of such botnets. We first, introduce OnionBots, what we believe will be the next generation of resilient, stealthy botnets. OnionBots use privacy infrastructures for cyber attacks by completely decoupling their operation from the infected host IP address and by carrying traffic that does not leak information about its source, destination, and nature. Such bots live symbiotically within the privacy infrastructures to evade detection, measurement, scale estimation, observation, and in general all IP-based current mitigation techniques. Furthermore, we show that with an adequate self-healing network maintenance scheme, that is simple to implement, OnionBots achieve a low diameter and a low degree and are robust to partitioning under node deletions. We developed a mitigation technique, called SOAP, that neutralizes the nodes of the basic OnionBots. We also outline and discuss a set of techniques that can enable subsequent waves of Super OnionBots. In light of the potential of such botnets, we believe that the research community should proactively develop detection and mitigation methods to thwart OnionBots, potentially making adjustments to privacy infrastructure.Comment: 12 pages, 8 figure

Bad Data Injection Attack and Defense in Electricity Market using Game Theory Study

Applications of cyber technologies improve the quality of monitoring and decision making in smart grid. These cyber technologies are vulnerable to malicious attacks, and compromising them can have serious technical and economical problems. This paper specifies the effect of compromising each measurement on the price of electricity, so that the attacker is able to change the prices in the desired direction (increasing or decreasing). Attacking and defending all measurements are impossible for the attacker and defender, respectively. This situation is modeled as a zero sum game between the attacker and defender. The game defines the proportion of times that the attacker and defender like to attack and defend different measurements, respectively. From the simulation results based on the PJM 5 Bus test system, we can show the effectiveness and properties of the studied game.Comment: To appear in IEEE Transactions on Smart Grid, Special Issue on Cyber, Physical, and System Security for Smart Gri