We are interested in cyber-physical systems (CPS) security. We have shown that various types of sensors (i.e. MEMS sensor, light sensor) can be compromised by diverse kinds of physical stimuli and sensor attacks can lead to lethal outcomes to CPS such as unmanned aerial vehicles (UAVs) and autonomous cars. We still focus on finding novel security problems in sensors, and we are also studying how to detect and defend sensor attacks. Besides sensor attacks, we have studied the impact of GPS attacks on CPS such as UAVs and power grid, and we are also interested in defending and detecting GPS attacks.


Most of the telecommunication systems carry data through data plane (for forwarding data) and control plane (for routing to the right destination). Therefore, disabling control plane may cause whole network breakdown. For example, our NDSS'11 paper shows that one can shut own the whole Internet with only 250K botnet. In this research, we focus on control plane security of current and emerging telecommunication infrastructure such as 3G, 4G LTE cellular communication, Internet, and future Internet. Among others, we are currently focusing on security, robustness, and accounting issues on these networks.


This is as a service to Korean community. We are helping 1) companies to find security problems of their products, 2) government to evaluate security of cyber infrastructure. For example, we are currently evaluating security problems of significant number of Korean smart phone apps, and the result has been quite surprising. We are also looking at security of Wibro eggs, 3G Femtocells, and popular navigators. If you are interested, don’t hesitate to contact us.


Our research also consider security problems of other systems such as cloud/storage, anonymous communication system and censorship-resistant systems and so on. For example, we are currently evaluating door lock system to find security problems which can be used to unlock the door for unauthorized person to enter the room. Moreover, we are also analyzing analog sensors to explore security problems which can be used to cracked the automobiles.