Biblio

We consider information leakage to the user in private information retrieval (PIR) systems. Information leakage can be measured in terms of individual message leakage or total leakage. Individual message leakage, or simply individual leakage, is defined as the amount of information that the user can obtain on any individual message that is not being requested, and the total leakage is defined as the amount of information that the user can obtain about all the other messages except the one being requested. In this work, we characterize the tradeoff between the minimum download cost and the individual leakage, and that for the total leakage, respectively. Coding schemes are proposed to achieve these optimal tradeoffs, which are also shown to be optimal in terms of the message size. We further characterize the optimal tradeoff between the minimum amount of common randomness and the total leakage. Moreover, we show that under individual leakage, common randomness is in fact unnecessary when there are more than two messages.

Internet of Things (loT) is network connected “Things” such as vehicles, buildings, embedded systems, sensors, as well as people. IoT enables these objects to collect and exchange data of interest to complete various tasks including patient health monitoring, environmental monitoring, system condition prognostics and prediction, smart grid, smart buildings, smart cities, and do on. Due to the large scale of and the limited host processor computation power in an IoT system, effective security provisioning is shifting from software-based security implementation to hardware-based security implementation in terms of efficiency and effectiveness. Moreover, FPGA can take over the work of infrastructure components to preserve and protect critical components and minimize the negative impacts on these components. In this paper, we employ Xilinx Zynq-7000 Series System-on-Chip (SoC) ZC706 prototype board to design an IoT device. To defend against threats to FPGA design, we have studied Zynq-ZC706 to (1) encrypt FPGA bitstream to protect the IoT device from bitstream decoding; (2) encrypt system boot image to enhance system security; and (3) ensure the FPGA operates correctly as intended via authentication to avoid spoofing and Trojan Horse attacks.