Information leakage occurs when an entity (e.g., system,  protocol, hardware, software) unknowingly gives off more  information than intended during normal operation (or  communication for my interest). Network traffic generated by  the transmitting parties can be passively monitored.  Information  about the entity that generated the traffic can  then be extracted  from the captured traffic. This information  can be used to: (1)  secure computer systems; (2) attack  computer systems; and (3)  improve the performance of  certain types of  networks (e.g.,  grid networks).

 As defined by Webster, steganography is the art or practice of  concealing a message, image,   or file within another message, image, or  file. Network steganography involves concealing a message in  normal  traffic on the network. Many of the current network protocols  are  considered non-deterministic. Non-deterministic systems can be  modeled as a set of states and state transitions that have a given  probability. Therefore, any system that can be modeled as such is  vulnerable to covert channels. Our work in this area involves creating  algorithms capable of generating covert side channels that exploit this  non-determinism and that have little probability of being detected. This covert communication has many applications, including sending information while evading traditional intrusion detection systems. We have developed various types of covert channels for wired and wireless systems at the network and MAC layers.

 Wireless networks differ from wired networks in several ways  including: (1) node proximity – attackers often are physically  close to victims in wireless networks; (2) signal propagation –  the wireless link is inherently insecure as it broadcasts  traffic,  giving surrounding nodes an opportunity to  eavesdrop; (3)  resource constraints – often the devices on a  wireless network  have a finite amount of power supplied by a  battery and have  limited processing and transmission power  (e.g., sensor  nodes);  and (4) mobility – wireless nodes often  have varying  levels of  mobility. As a result of the above differences between wired and wireless networks, techniques for providing security in wired networks cannot be directly applied to resource-constrained wireless networks. Our work in this area involves the development of resource-aware security protocols for various wireless networks.

 Ensuring that network protocols operate efficiently is a  challenging problem. This challenge is heightened as networks  become large and distributed or operate over a wireless  medium. Our work is this area involves designing efficient  protocols that reduce network overhead and energy  consumption of wireless devices, and improve the overall  performance of the network.