A side-channel is any process that inevitably and unintentionally leaks information to an unauthorized user in a computer or communication system. A covert channel is any mechanism through which two parties simultaneously accessing the same computer intentionally communicate, despite this mechanism being disallowed for communication. Examples of both channels abound, and their presence makes our computation and communication infrastructure less secure: side channels allow attackers to glean sensitive information that they would not otherwise be able to access, and covert channels enable unauthorized disclosure between users. This project enables engineers to attenuate side- and convert channels, thereby making our electronic infrastructure less vulnerable to external attack and internal leaks. In the process, the project enables a new collaboration between researchers in information theory, computer architecture, and communication networks. The project broadens participation of under-represented groups, especially women, through research opportunities and an improved mentoring program for a professional society. This project approaches the study of side- and covert channels information theoretically. Historically, information theory has provided relatively little assistance toward mitigating side- and covert channels. This is partly because it is unclear how to quantify the amount of information leaked through a side channel and partly because many side- and covert channels involve a receiver that can actively control the channel. Such receivers are not well understood. To address these two impediments, the project develops a recently-proposed metric for measuring leakage in side-channels that is operationally justified and easily computed. The project also develops results that enable one to predict how active receivers will act. The project culminates in the application of these results to three specific scenarios spanning communication networks and multi-core processors.
CIF:Medium:Collaborative Research:Maximal Leakage and Active Receivers for Side- and Covert Channel Analysis